River confusion

[sean c]

FT 2/4. Not been at the table long and the button hasn't stood out in any way.

Pre flop: 3 folds, button raises, I 3-bet A [img]/images/graemlins/spade.gif[/img]8 [img]/images/graemlins/spade.gif[/img], BB folds, button caps and I call.

Flop(2 players 9sb): 2 [img]/images/graemlins/spade.gif[/img]4 [img]/images/graemlins/spade.gif[/img]9 [img]/images/graemlins/club.gif[/img]
I check/call.

Turn(2 players 5.5bb): K [img]/images/graemlins/diamond.gif[/img]
I check and he checks behind.

River(2 players 5.5bb): K [img]/images/graemlins/heart.gif[/img]
I?