Stack Sizes: CO $520, Button $670.

I've got a LAGGY image and have been running over the table the last few rounds. PreFlop CO raises to $12. I call with , the SB folds and the BB calls. The Flop comes:



the BB checks, CO checks, and I decide to take a stab at it and bet the pot, BB folds and CO calls. The Turn comes the giving me a straight, but also making a flush.

CO checks. What's my play?