Harrowing way to bust out

[HalfSugar]

It was only a $10 f/o tourney but were in the last 45 or so from 509. I had maybe 11K going into the hand at 400/800 and BB was all-in for less than the SB. UTG I pick up KK and make it 2,600. Two seats call, flop is KQ5. I push for a pot sized bet one of the callers calls. He shows AA, turns an Ace and then I notice that the BB has the case K. FML