I'm sooooooooo friggin' pissed

[bestcellar]

FT (8 left) of the Paradise Ocean tourney this morning. The previous hand a player in MP had been knocked down to 400 in chips with the blinds 600/1200 with 50 antes, so I'm already counting 7th place money. At most he has 3 hands left till he's all in. I have about 6.5k, and as I post my 1200 bb I wake up with AdKd. UTG, the big stack (about 50k) limps in for 1200 and it's folded around to me. I move, of course. He thinks about it for a while, and as he's thinking I feel I have him dominated and put him on Ax. He calls. He has Ac7c. The board runs out and he ends up with a J high straight (gutshotted on river). The flop did not bring an ace. I know everyone will probably say I made the right play, but moving there cost me $47 (8th was $93, 7th was $140).

Should I have played this differently, or is this just a bad beat, move on? Regardless of whether my opp has Ax and I have him dominated (say he has QJ or QT), should I have waited the shortstack out despite my premium hand? I knew he would call, in fact I wanted the call as I knew I was probably ahead and hoping I had him dom.