NL50 - AA facing 4Bet All-in

[niteswmer]

Villain is 35.7/4.2/.57 over only 42 hands. I've been finding that many villians at this level tend to automatically put people on AK and get aggressive on the flop, but villain's 4Bet makes me think he may actually have something here as lots of hands beat me here. Only thing I'm beating is TP or str8 draw(which I've seen pushed in this situation a lot). I really want to call, but should I just fold?

Full Tilt No-Limit Hold'em, $0.50 BB (9 handed) Full Tilt Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

MP2 ($15.65)
MP3 ($23)
CO ($26.70)
Hero ($64.30)
SB ($9)
BB ($60.40)
UTG ($53.80)
UTG+1 ($55.25)
MP1 ($58.50)

Preflop: Hero is Button with A[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/heart.gif[/img].
<font color="#666666">6 folds</font>, <font color="#CC3333">Hero raises to $1.75</font>, <font color="#666666">1 fold</font>, BB calls $1.25.

Flop: ($3.75) 7[img]/images/graemlins/spade.gif[/img], 3[img]/images/graemlins/heart.gif[/img], 6[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
BB checks, <font color="#CC3333">Hero bets $3</font>, <font color="#CC3333">BB raises to $9</font>, <font color="#CC3333">Hero raises to $22</font>, <font color="#CC3333">BB raises to $67.65 (All-In)</font>, Hero ???