The problem is that I get hit after I roll. Can you block instantly right after you roll, or is that there some vulnerable frames? It might because they're hitting me high, and I'm just not paying attention.
I consider myself pretty bad at fighters (probably because my first fighter was IaMP) and I don't know how okemi or whatever it's called works. If I try anything to get out of the corner after knock down, I usually get hit. How do you defend against blockstrings and when do you attack back? Do you just have to know the other character's blockstrings?