Another AK question

[helloitsme]

This is one of those 1-2 100 Max buy-in no limit games. There has been some wild play followed by some rockish play, followed again by some wild play. 3 guys have HUGE stacks, the rest have about 100 or 150. I have about 175 after some really nice hands hit my in the head. So, I sit on the dealer button with AK [img]/images/graemlins/club.gif[/img]. There were 3 limpers so I raise to 15. The small blind folds, the big blind calls, the others all call. The flop is K 9 4 rainbow. It is checked to me. I make a pot sized bet, the big blind raises. Now, I have seen this character play all sorts of hands, you know Ace anything, K anything, etc. I have also seen him try to steal pots almost every hand he is in. So. . . I push. Now he instantly calls and turns up K9 off suit. I have AK [img]/images/graemlins/club.gif[/img]. We go the the river, he wins. I take another 100 out of my wallet and say "nice hand." Although I meant "OH MY GOD HOW DID THAT JUST HAPPEN? I HATE THIS GAME!!!!" My question is, should I have folded or did I do the right thing? If I just call, I would have had about 40 left, so I went all in. Is this just one of those things or did I make a tactical mistake along the way? Thanks.