QJs on the Button with 20 BBs

With 16 players left and 11 getting paid I was at 20 BBs on the button with QJ diamonds. 2 people limped and I just called thinking it would a take 4-5 BB to take it down and would have to a fold with a re shove. My first question is should I have raised. I limped with a great speculative hand. The small blind called and the big blind checked. The flop came a J-7-6 with two diamonds. Top pair and flush draw. Great. Three checks and a 12K bet. I shoved. Second question - call, raise (STP ratio problem) or shove. Everyone folded and he said I guess I need to call. He had A2 od diamonds. Probably thought he had 12 outs when in fact it was 10 outs. He risked half his stack on a draw. Turns out I was 62%. King of diamonds hit the turn. Had I called all the money was going in after the turn. Analysis please.