Does anyone fold somewhere with overpair?

I never ever fold this even if I get checkraised. Is this a leak?

On the river I took a shot at him having two pair, which got counterfeited or him just trying to push me out with top pair. Comments please

UTG is 41/10/1.33 over 200 hands and a typical gambler

Ultimate Bet 3/6 Hold'em (6 handed) converter

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

Flop: (4.33 SB) 9[img]/images/graemlins/heart.gif[/img], 7[img]/images/graemlins/heart.gif[/img], 3[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, UTG calls.

Turn: (3.16 BB) T[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, <font color="#CC3333">UTG raises</font>, Hero calls.

River: (7.16 BB) 3[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, <font color="#CC3333">UTG raises</font>, Hero calls.

Final Pot: 11.16 BB