6 handed on UB, $50 NL.

I'm on the button with [9s], CO limps and I limp too. Normally I'd raise here but I had been raising a lot in LP without much success, so I decided to limp for a change. Both blinds complete, everyone has more or less full stacks.

Flop: [9d][6h]. Blinds check, CO bets $1.50, I raise to $6. Only CO calls. Previous time I raised his flop bet I had Q7 on a QT7 board, the turn brought another T and I folded to his potsized bet.

Turn: . CO immediately bets $10. I'm not sure where I'm at here and flat call. I think that he would play the flush like this, but I guess I'm often enough good here to look him up.

River: . Check-check and I lose to [5d].

Raise bigger on the flop? Push turn?