My mother passed away May 30. My dad's actions have changed since then. Anyone else experience this?

I agree, a physical would be good. And perhaps, at least temporarily, anti-anxiety meds would be helpful.

But, gosh, this poor man lost his life partner less than 2 months ago. Weren't you expecting some disturbances? Mourning takes many different forms. Some people have cognitive issues. (I did. Didn't cry but had memory problems for months. I was surprised to learn that was a "normal" way of experiencing grief.)

He deserves a good checkup, and medical support if necessary. But it sounds to me like he needs a lot more time to adjust to being a widower.

The majority of widowers have a harder time than widows. It's hard regardless of which. I'm sorry for your loss too. It's so hard to lose your Mom and on top of it see the impact on your Dad. My Dad is still struggling with the loss of his best friend, partner, lover, bill payer, meal maker, organizer of every little thing in life he didn't have time to do while he was working. She did it all. Raised us kids, the whole nine yards and then some. After eight years he is finally talking about her and how much she meant. He isolated to extremes. Falling ill allowed him to let go and open up more than he has in years.
Huge hugs to you. It's not easy.

Some elderly couples will function better when together. They can compensate for each others weaknesses so that when they are together you don't notice.
After losing a spouse with all of the other reasons already mentioned it may be impossible to conceal the loss of cognitive abilities. This can also contribute to stress because the partner is not there to support them.

Grief does a number on a person. It's hard to eat and sleep after you lose someone, and that in itself, poor sleep, or digestive problems (meaning you might be eating but you don't really ingest or properly use what you take in) on top of grief can make it hard to think straight. You'll forget stuff more easily than usual, maybe be accident-prone, too. All that is pretty much to be expected, especially insomnia. I wouldn't be too quick to rush to the pharmaceuticals. Many of these are not safe for elderly people and only make things worse due to side effects. Why medicate normal grieving? It's not a disease. Time and time alone will take care of it. You cannot rush it nor set a time limit nor demand that a person snap out of it. Some take years, while others bounce back more quickly, and it's not a moral issue if you take longer, nor any indication of weakness of character, nor any measure of the strength of love toward the one who has passed. It simply is.

FF is right, the hand tapping is anxiety. Old people can literally die of a broken hear. Get him a complete physical soon.

If this is the only thing that has noticeably changed after the trauma of losing his life partner he is fairing pretty well. It could be a symptom of stress, boredom or a manner of comforting himself. When my father died my mother began falling and could not get up. A couple of ambulance rides and me taking her to the ER a couple of times made me think we were on the downhill slide. But it they all happened with in 2-3 months of Dads passing. It has been about 3 years since she has fallen and I think this was a manifestation of her grief and feeling lost without him. A check up is wise, but I suspect he also needs some activity and ways to socialize. It is not uncommon for widowers and widows to find fewer invitations coming their way once they lose their spouse. Consider ways you can help him create a full life in his new situation. He may need help thinking through his interests and options.

The patting of his hand sounds like he is trying to release some stress. Is your Dad mobile? If so, have him keep himself busy to let loose of that energy.... I know that is easier said then done [I need to take my own advice for myself].

Also, if he hasn't already, time for a check up with his primary doctor.

nothing worse than losing a loved one!!! the grieving process is a killer...not to mention that spouses have died shortly after their loved ones passed from a broken heart!!! soooooooooooo sad!!

Depending on your culture, death rituals for the loss of a spouse can take up to one year. The purpose of death rituals is to help the living. Your dad is in mourning. What have you, other family members, and friends been doing to help him come back into the fold? Small things like sharing a meal or calling him or inviting him out for a stroll help let him know he's not alone in his grief.

I would recommend a dog to anyone! If your dad doesn't have one, bring one to him because they seem to have abilities we humans cannot even fathom.