I've had these memories myself, and personally I don't think they're part of any mental illness. I think everyone has these memories that they're embarrassed about.
We all do things when we're young that we want to forget. We're impulsive as a young person, and don't use good judgment. We aren't old enough to even HAVE good judgment.
So don't think you're the only one who has these kinds of memories. Millions of people have these, and would just as soon forget them.

Some of us CAN forget them, while others seem to bring them forth every now and again, and embarrass ourselves all over again. Don't worry about it. It's NOT anything serious -- at least that's MY opinion.
Take care and talk to your therapist if you're really bothered. God bless. Hugs, Lee