Should I have pushed here?

[semperfi]

$20 6 handed SNG on Pacific. Early in trny, $20BB, I have not played a hand. Everyone has 800-1200 chips. I limp behind 2 callers w/ KQ spades in the SB, BB checks. Flop comes KKA w/ 2 hearts. I bet the pot, in case there is a heart draw out. MP limper calls, button raises the pot. I don't like to get all in against a flush draw on the flop, but I figure MP most likely has a draw, and may fold behind two raisers, and the button most likely has an Ace which is only a two outter, if he has AK or AA oh well. I push, and both call!. The opponents had what I suspected, and of course the A comes on the turn, and my full houses loses. I am out 6th. These are typically very weak players at Pacific, was I wrong to take a shot at doubling or tripling up early?

[semperfi]

I just realized that once I went all in, the flush draw was getting about 2 to one, even if the button folds, with two cards to come. Does that make his second call correct even though a full house was possible, especially with two others in the pot?