AA deep, facing tough spot

[teh_sponge]

PokerStars No-Limit Hold'em, $0.25 BB (6 handed) pokerhand.org hand converter

Villain just go to the table about 10 hands ago, min raise is his standard raise pf

CO ($22.15)
Button ($14.40)
Hero ($35.15)
BB ($8.85)
UTG ($25.60)
MP ($49.65)

Preflop: Hero is SB with A[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">1 fold</font>, <font color="#CC3333">MP raises to $0.5</font>, <font color="#666666">1 fold</font>, Button calls $0.50, <font color="#CC3333">Hero raises to $2.5</font>, <font color="#666666">1 fold</font>, MP calls $2, Button folds.

Flop: ($5.75) 4[img]/images/graemlins/diamond.gif[/img], 5[img]/images/graemlins/spade.gif[/img], 2[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $4</font>, MP calls $4.

Turn: ($13.75) 2[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $9.25</font>, <font color="#CC3333">MP raises to $18.5</font>, <font color="#CC3333">Hero ???