It's not officially abuse if you were both under age, especially if she was about your age also. Sounds pretty young if you stopped when she could get pregnant, 13 or so. Sounds like two unsupervised pre-teens/teens getting in over their heads without swimming instructions.

I don't think you are messed up; the dreams were trying to help you understand it was not a good idea, that there is more to sex than just feeling good. If you are having problems relating to women now, I would go see a therapist and discuss it all.