I cant tell u if its a dream or not. I know what ur going through cause i have a memory but it was when i was very little and a boy put his hands down my pants. It didnt pop up into my mind untill i started to get physically beaten in school. I dont know if it was a dream either. I do know how frustrating it is. It could be a repressed memory that was triggered to surface by something.
thats all the advice i can give.