200NL - But I don't wanna fold

[spivey]

Villain is unknown, no reads - he just sat down about an orbit ago. But I think he bought in around 85BB or so, so he may suck.

Full Tilt Poker, $1/$2 NL Hold'em Cash Game, 5 Players
LegoPoker Hand History Converter

BTN: $392
SB: $271.70
Hero (BB): $217.30
UTG: $217.20
CO: $157.85

Pre-Flop: 3[img]/images/graemlins/diamond.gif[/img] Q[img]/images/graemlins/spade.gif[/img] dealt to Hero (BB)
UTG folds, CO calls $2, 2 folds, Hero checks

Flop: ($5) 6[img]/images/graemlins/diamond.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] 7[img]/images/graemlins/diamond.gif[/img] (2 Players)
<font color="red">Hero bets $3</font>, CO calls $3

Turn: ($11) Q[img]/images/graemlins/club.gif[/img] (2 Players)
<font color="red">Hero bets $7</font>, CO calls $7

River: ($25) A[img]/images/graemlins/spade.gif[/img] (2 Players)
<font color="red">Hero bets $12</font>, <font color="red">CO raises to $42</font> Hero?

Turn bet may be a little weak. River I bet small hoping Ad may call, or AxXd may call. Do I need to fold here? Can he be bluffing here enough to call?