Bluff or not?

[mute]

Villain is 26/14/1.5. I have been running well and haven't been caught bluffing, but have also won a fair share of pots not showing down. Worth it?

Party Poker 15/30 Hold'em (6 handed) Hand History converter Courtesy of PokerZion.com

Preflop: Hero is SB with 6[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">4 folds</font>, <font color="#CC3333">Hero raises</font>, BB calls.

Flop: (4 SB) 8[img]/images/graemlins/diamond.gif[/img], 8[img]/images/graemlins/heart.gif[/img], 9[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, <font color="#CC3333">BB raises</font>, Hero calls.

Turn: (4 BB) 2[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, BB checks.

River: (4 BB) K[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero...