Should I raise this? AA river question

[AmonRaa]

I've been at the table for 5 min. Just came for quick fix so no reads.

Full Tilt No-Limit Hold'em, $0.25 BB (9 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

UTG ($11.15)
UTG+1 ($20.90)
MP1 ($17)
MP2 ($7.60)
MP3 ($27.60)
CO ($5.30)
Hero ($25.80)
SB ($25.40)
BB ($17.80)

Preflop: Hero is Button with A[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/spade.gif[/img].
UTG calls $0.25, <font color="#666666">1 fold</font>, MP1 calls $0.25, <font color="#666666">3 folds</font>, <font color="#CC3333">Hero raises to $1.5</font>, <font color="#666666">2 folds</font>, UTG folds, MP1 calls $1.25.

Flop: ($3.60) 7[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
MP1 checks, <font color="#CC3333">Hero bets $2.4</font>, MP1 calls $2.40.

Nice flop I guess. Cant see villain having a 7. Was a bit tempted to check behind here as I didnt see with what can villain call but I'd cbet this with AK so no need to deviate.

Turn: ($8.40) Q[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
MP1 checks, Hero checks.

I didnt really see the need to bet here. There are no draws. Either he has me crushed or villain has sth little (medium pp) he wont call a bet with.

River: ($8.40) 6[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">MP1 bets $6</font>, Hero calls $6.

Villain leads into me. I'm good or I'm not. I can see him having a Q and since he hasnt got a lot behind he might call a raise. If he was deeper I think raise would be wrong since he wouldnt call it with just a Q but in this instance it might be ok. I wussed up and just called.

Final Pot: $20.40