Last night I was at a kickback and there was this super cute chick that I had gone to high school with there (we had never really talked in hs). We kinda flirted throughout the night and were teasing each other and all of that shit. She seemed pretty interested in me and gave several IOIs. Before I could do any more work my friends decided to leave really suddenly so the whole thing was kinda cut short. I fb messaged her and had the following interaction (I had been teasing her on her bp abilities as she was playing):

Me: So when did you guys end up losing and/or did you manage to get the ball without me? >:)

HB: on the last cup! hahaha we didnt loose any balls!
hahah

Me: Hahaha verrry impressive. I think after all of that shit talking last night we might have to play each other one of these days and establish once and for all who is the superior pong player

HB: down. lol

What should I do now? Ask for her number or what? Is there stuff I should have done differently?

Or I guess a more simple question is should I just ask for her # over fb or what?

I'd invite her via fB. That way she'll easily give you her number.