SB looks like he has either AK or JJ. Raising pre-flop and then not following up with a continuation bet usually means he completely whiffed and doesn't want to bet into 2 people, or he's got a monster and is trying to check-raise. But then he doesn't check-raise your flop bet and he wakes up on the turn when the A hits, so AK is looking more likely.
As far as your hand, I have no idea.
I don't see you raising any flush draw ([Kc] x[c]) hands from early position like that because the
is already out there (I guess it could be
), and the only straight draw on the flop - 57 or 79 - aren't ones you'd normally raise from EP, either. Unless it's something like
... You bet your draw on the flop when it's checked to you, you only call a 1/2 pot-sized bet on the turn when it looks like he paired his Ace, and you call an all-in on the river when both the flush and straight draws come in (so you could have 79 suited in something else, I guess)