Oh yeah, maybe it is an Aspie thing. I think it is a combination of worrying, obsessing, and trying to be a perfectionist and analyse the situation over and over again to try and make sense of it. I know I always do this! and it really drives me nuts.
I don't know if I so much worry about the past events, the past is in the past, but if it was really devastating to me and I feel I should have done something better, than yeah, I will have obsessive thoughts about it. But more so I tend to obsess and worry about the what IFS, I worry about what may happen, what I think definitely will or could happen, and I get this strong anxiety and I try to think and think of how to get myself out of that situation, or what am I gonna do, and it is very stressful! College was so extremely stressful for me, because I had to produce good work but I wasn't very fast or very good at some things, and I was trying to find opportunities to make friends, and I was also very obsessed with one guy as I wasn't used to having a crush and didn't know how what to do about it, and then worrying about how to talk to him caused me to not focus on my work, etc. Oh dear, that was really an ugly mess, I think I went home crying on many days.