Tell me if I went wrong

Hi there. I don't have the hand history sorry but can someone tell me what they think of my play, whether it was sensible or bad please? I am in an MTT the blinds are only 30 60 with an 8 minute blind level. I am in 2nd place I have approx 16200 chips leader has 16500. I am sat in big blind with KJ unsuited. 3 players make a 60 bet. Chip leader raises to 180. A few folds. CO calls he has 3700 chips, Small blind folds. I decide to call. Flop comes K 9 6 all mixed suit. I check hoping for a bet from someone. Then to my surprise chip leader bets 5000 and CO calls all in What do I do? I mean what can they have? I think somebody must have AK KQ possibly even trips so i fold. If i call chip leader is surely going to bet more on the turn so my K may be no good. I decided to preserve my chips and get out of the hand. Turn card was a 5. River a 2. Chip leader shows K4 and wins the hand CO has 7 10 suited. I would of won the hand and 22000 chips had I stayed in and a massive chip leader. So was I correct to fold? Or sensible?