You are playing this hand way too passively. Raise somewhere!!!! Just to find out how strong your opponents are. In a 6 handed game KK is an ABSOLUTE MONSTER preflop, and still is big after the flop. You have to play this hand more aggressively. You have to raise the flop the size of the pot here. Make them pay if they are on a draw. You may have taken the pot down on the flop if you did that.