When to fold Ace high?

[handsome]

Party Poker 2/4 Hold'em (10 handed) converter

Preflop: Hero is MP2 with A[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/club.gif[/img].
<font color="#666666">4 folds</font>, <font color="#CC3333">Hero raises</font>, <font color="#666666">2 folds</font>, Button calls, SB calls, <font color="#666666">1 fold</font>.

Flop: (7 SB) J[img]/images/graemlins/heart.gif[/img], J[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, <font color="#CC3333">Hero bets</font>, Button calls, SB folds.

Turn: (4.50 BB) T[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets</font>, Hero calls.

River: (6.50 BB) 4[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets</font>, Hero folds.

Final Pot: 7.50 BB

Villain is fairly loose preflop. Postflop I dunno. I felt fairly disgusted after this hand. When I was playing it, I wasn't sure if I should've called down or folded earlier.. and by the river I knew I couldn't beat anything but a bluff. Insight?