He might not remember everything, hell, he might only remember bits and pieces, but his concern is likely whether or not you remember anything.
I've wondered what I would say if I ran into him somewhere.
But this is a great friend and a friendship worth salvaging.
I think 11 seems young to be experimenting, but that could be me.
I always love making out with girls.
I have never been intoxicated enough to not recollect my actions, especially engaging in sex with someone, and I sincerely doubt the honesty of anyone who claims such complete and total memory loss.
If your friend starts hitting on you, then it would probably be a good idea to have a conversation about what happened.
Educate Yourself The more insight you get, the more clarity and comfort you'll receive about any confusion you have.