25NL:Flop Trips, Villian wakes up on river

[Alfil]

Villian sat a little more than three orbits ago and won a couple of small pots without a showdown and I have only entered 2 pots in that time.

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.10/$0.25
6 players
Converter

Stack sizes:
UTG: $7.15
UTG+1: $19.95
CO: $31.75
Button: $27.10
SB: $13.85
Hero: $34.95

Pre-flop: (6 players) Hero is BB with 9[img]/images/graemlins/heart.gif[/img] T[img]/images/graemlins/heart.gif[/img]
2 folds, CO calls, Button folds, SB calls, Hero checks.

Flop: 9[img]/images/graemlins/diamond.gif[/img] 9[img]/images/graemlins/club.gif[/img] 2[img]/images/graemlins/club.gif[/img] ($0.75, 3 players)
SB checks, Hero checks, <font color="#cc0000">CO bets $0.5</font>, SB calls, Hero calls.

Turn: 3[img]/images/graemlins/spade.gif[/img] ($2.25, 3 players)
SB checks, <font color="#cc0000">Hero bets $2</font>, CO calls, SB folds.

River: K[img]/images/graemlins/heart.gif[/img] ($6.25, 2 players)
<font color="#cc0000">Hero bets $4</font>, <font color="#cc0000">CO raises to $14</font>.

Hero ???