Can a hospital give too much fluids to cause CHF?

You had fluid overload. It can happen, yes. Somehow your systems were in a fragile state due to your hospitalization.
If you were found to have fluid overload they will want to watch your heart and your kidneys. I hope they suggested they follow you in 3-6 months.

As an RN I can tell you there are few things so scary as not being able to breath. But you had a good report and have a good ejection fraction, so it is clear that, unless anything else happens, you are for now in the clear.

Anxiety can affect your breathing. I think you will calm out of this. If you don't return to the doc for more reassurance.

I just went through the kidney stone surgery and stent thing in the past year. I'm glad your CHF was diagnosed so that you can manage it wisely. I was counting the days when the post-op stent would come out!

Daughterof1930 gave you an excellent explanation of CHF. Don't be scared all the time, there's no need. My cousin has lived 25 years already with CHF and my mother lived to 95 years old with it. You just need to limit your fluid intake, most likely, but the cardiologist will advise you on that. With a good EF, you're likely to live a long time! Definitely make an appointment for a follow up with the cardiologist and establish a relationship with him.

Good luck to you.

My adult son is a lifelong heart patient. He’s certainly been given too much IV fluid at times and become fluid overloaded and also had too much fluid pulled off with IV Lasix and become dehydrated. Same for my dad with his years of CHF. Fluid overload is a part of CHF as the heart is a weakened pump. It’s more likely as you were given fluids to help flush the kidney stone and keep you hydrated, a side effect was the discovery of CHF being present. I hope you’ll have a follow-up cardiology appointment to have further evaluation and gain a better understanding of your condition