During the three weeks I've been away, I posted a few general "touristy" updates on this blog. I refrained from reporting what was actually going on, not wanting to alarm my nearest and dearest. Now that I'm back, I can tell the real story.

So, what was going on?

I arrived at my initial stop—Santiago, Chile—absolutely wiped out. The usual jetlag was exacerbated by an 11-hour layover in Miami. During my 36 hours in Santiago, before boarding the ship in Valparaiso, I ventured out of the hotel a few times, but I needed to stop and rest on benches during each brief walk.

On the ship, I developed a new problem that persisted through the trip. I'm addicted to the internet and this blog, so I'd brought along my Lenova ultrabook, which I knew from my trip to Europe last summer had problems. Those issues got worse on the ship. A computer geek onboard identified the problem: my Lenova has both a touchpad and a keyboard. The touchpad is highly sensitive to keyboard strokes, so the cursor kept jumping around. Unlike most machines, the Lenova doesn't have a way to deactivate the touchpad.

High internet charges and high blood pressure

That was bad enough, but Holland America also charged 75 cents a minute for internet access. They did offer a discounted price if you bought 100 minutes or more, which I did.

As I struggled with the computer and paid the hefty internet charges, my blood pressure readings began to rise above 150/90—considered the upper limit for someone my age. I'm sure that stress caused the bp spike, but the internet issues didn't help.

I had packed a wrist blood pressure monitor because I carefully monitor my numbers. I recently ditched the bp pills when I discovered that two electronic devices—recommended in last December's Mayo Clinic Health Letter -- seemed to work for me.

I was also experiencing the increased mobility and balance problems that typically accompany Parkinson's disease. I shortened the interval between my medication doses through the day, from six hours to five, but it was hard to tell whether that helped.

On a shore excursion at the start of the trip, I had a bad fall. We were walking down a wooden pathway back to the shuttle boat when I stumbled on a crack between the planks. Although I landed on my side and rose immediately, I ended up with pain in my sternum that persists. I'll schedule an appointment with my internist soon.

I knew the fall caused the pain, but having high blood pressure readings and chest pains was a bit disturbing.

As we sailed on, my blood pressure became increasingly erratic. I saw a reading of 200/100, which is stroke territory. It wasn't just those high numbers; I felt crummy.

An unpleasant, familiar problem

At the last stop—Punta del Este, Uruguay—I experienced an incident I'm certain was due not to high blood pressure, but to a sharp drop in bp. After bouncing to and from the sea lion island in a boat through rough seas, I had time for a walk around town before catching a shuttle boat back to the ship. It was midday, and we were experiencing our first warm day of the entire trip. I was OK for the first part of the walk, but I was completely wiped out when I tried to return. I had to find something to hang on to every step of the way.

I had experienced this same disturbing phenomenon at home last summer: I'd have major sinking spells—close to passing out—while doing any sort of physical exertion outdoors on warm days. The problem stopped when the weather cooled. But the warm day in Uruguay brought it back. My research last fall identified the cause of the problem, and—as we head toward summer in DC—I'd better prepare for its return.

I fell in love right away with Buenos Aries, where the cruise ended. I checked into my terrific apartment in the city's nicest neighborhood (more about that later). I thought about extending my stay, and even wished I had junked the cruise and just planned a couple weeks in Buenos Aires. But health issues flared up again. The high blood pressure readings got worse, and so did the fatigue.

Beware: sharp turn ahead

Fortunately, I was able to take a five-hour bus tour of the city and enjoy good lunches and suppers in several very good small cafes close to my apartment.

Then came the final mishap.

I was going to dinner at a recommended neighborhood restaurant, four blocks away. It wasn't easy. I walked past the restaurant, turned back, finally spotted it on the other side of the street, and made a quick turn to cross the road. I'd forgotten that quick turns are the biggest threat to my balance these days. Combining a turn with the forward-leaning posture that comes with Parkinson's can lead to trouble. I lurched forward, hurtled across the street, and landed flat on my face at the door of the restaurant.

Talk about a dramatic entrance!

The proprietor and several waiters came out and helped me into the restaurant. I ended up having one of the best meals of the trip, but I ordered a cab for the trip back to the hotel.

The next night, my last in BA, I was looking forward to a scheduled dinner and tango show. But, the weakness I felt after the fall made me decide to skip the 6:00 pm-midnight event. I wanted to be damn sure I was able to get on the flight home the next day.

So, what caused these problems? I did.

With my 85th birthday in May approaching, it was crazy to take a three-week trip alone, so far from home. I wanted to see South America before I go, but part of the reason for this trip was showing off.

"Hey, look what this 84-year-old with Parkinson's can do!"

Doing it solo was a big part of the problem. I wouldn't have fixated so much on my blood pressure and other issues if I'd been traveling with a friend. Loneliness and depression became an increasing problem toward the end of the trip. .

On days at sea, I tried several times to meet others at the bridge table. The daily calendar always had a room set aside for people who wanted to play bridge. The first time I went, it worked. Another single man and I paired up for a good game with a couple. The next time I showed up, a couple was waiting for others to form a foursome, but soon another couple showed up, and I deferred to them. The same thing happened again. Cruises like this are primarily for couples.

Browse Our Free Senior Care Guides

Odd man out

I should have taken advantage of other opportunities to socialize. Each day's calendar listed a late afternoon meeting for "Friends of Bill W" (recovering alcoholics), and another for LGBT passengers. I should have given both a try.

Good friends—cruise veterans—told me they often met interesting new people by sitting at "open tables" for six to ten people. I tried it once. I joined two couples, and it was OK. But, as the single, I still felt the odd man out. In any case, I'm not interested in big fancy meals at set hours, particularly when traveling solo.

I'll reflect more on lessons to be learned from this experience. But here's an initial observation that popped up during this morning's 3:00 am "joy of quiet" hour.

John's energy bank

My energy supply is similar to the financial situation of someone my age who is trying to live on social security alone. What I have in the bank is limited, and replenished slowly in small amounts.

This trip depleted my energy bank and left me seriously overdrawn. It's going to take time to rebuild the reserve. While waiting for this recovery, I should reduce my current energy expenditures as much as possible.

Falls really drain the energy bank. Most of us have known elderly friends or relatives who seemed to be aging fairly well . . . until they had a serious fall. Then we've seen the aging process accelerate.

I've fallen before, stumbling on sidewalk cracks. With my "Parkinson's Walk"—shuffling along without really picking up the feet—it's surprising I haven't fallen more often. But this Buenos Aires restaurant tumble was my first pure, unadulterated Parkinson's fall. I know from my PD support group how frequent and debilitating these falls can become.

Developing strategies to avoid falling needs to be one of my top priorities.