Sexual Assault Legitimacy

When I was 13/14 I was sexually assaulted by the guy I was "dating" at the time. I put that in quotes because I was young and don't really count it. 
We were on the bus home from school one day and he pushed us down in the seat and kept grabbing my chest and crotch. Kept asking me if it felt good... I didn't even know what that meant. It escalated to him trying to fully reach into my clothes but thank god my bus stop came up and I got away... 
This is the first time I ever fully told this story because I always feel bad. The voice in the back of my head reminds me how much worse experiences other women have had and that I should just consider myself lucky... I was lucky to some extent... I'm 21 now but it still happened to me.