Top Pair, Flush Draw

live tournament, 120 players, down to 20 or so. avg. stack around 12 or 13K. my stack 9K.

loose player limps in. i'm on the button with KT suited(clubs). with two passive players in the blinds, i call. SB calls, BB checks. flop comes K, 9clubs, 5clubs. i obviously love this flop. SB checks, BB checks, loose player bets 1000. due to the size of his bet, i put him on absolutely nothing at all. plus the players in the blinds are not capable of a check-raise. i raise to 3000, blinds fold, loose player calls. worst possible card falls on the turn-- a red ace. he checks, i shove my last 5000 in. he calls, turns up A3. i do not improve on the river, get knocked out.

in retrospect, i should of went all in on the flop. is making just a small raise here a huge mistake?

i would appreciate some feedback.