I had 95o in BB, checked, and flopped a pair of fives and SB bet. I probably should have raised, but I didn't because there were a couple things that worried me. First of all, I was worried about how small my pair was since even though it was middle pair almost all the remaining cards would be overcards potentially giving him a bigger pair. Should this concern me?

EDIT: The flop was 5,Q,4 rainbow

Secondly, my postflop play isn't great and I would have no idea what to do if he reraised me. Should I just call or cap it? Also how would I play the turn and river if he reraised me? I assume I'd bet out on the turn if he just called the raise though.

SB had a VP$IP% of 36 and PFR% of 9.