Opened button with KK get called by SB and 3bet by the big stacked BB. Decide to call to keep SB in he calls. BB makes solid cbet. I call with the 2nd nuts on AK7 board trying to keep SB in looking for stacks, SB folds 9 comes on the turn giving a flush draw. BB makes a solid cbet and I figure its quite likely he has an ace high flush draw so I reraise to protect. BB shoves and I have to make a crying call praying he doesn't have AA. Nervewracking.