Yeah, definitely. I have a few memories like this. I can very clearly remember seeing the Easter bunny when I was a kid. Obviously this never happened, but I can describe the scenario and what the human-sized rabbit looked like. Also, I have a memory of my brother which is logistically impossible for me to have.

These are just examples of things I realize aren't real memories because the situations were never possible.

I was recently talking to some coworkers about a problem we had about 3 years ago. We all had different accounts of some of the details, but we were all about equally certain about our recollection of events. After digging through some old email, it turns out only one of the four of us was right.

The fallibility of our memories is something I think most of us significantly underestimate.