Not looking good but the pot is huge

[hoppscot22]

Full Tilt Poker $15/$30 Limit Hold'em - 6 players

Preflop: Hero is SB with A[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/diamond.gif[/img]
UTG folds, <font color="#FF0000">MP raises</font>, CO folds, Button folds, <font color="#FF0000">Hero 3-bets</font>, BB folds, MP calls.

Flop: (7.00 SB) J[img]/images/graemlins/club.gif[/img], 4[img]/images/graemlins/heart.gif[/img], 2[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#FF0000">Hero bets</font>, MP calls.

Turn: (4.50 BB) 3[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#FF0000">Hero bets</font>, MP calls.

River: (6.50 BB) Q[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#FF0000">Hero bets</font>, <font color="#FF0000">MP raises</font>, <font color="#FF0000">Hero 3-bets</font>, <font color="#FF0000">MP caps!</font>, Hero ...

So now the pot is huge, im getting like 12-1... firstly

river three bet.. good bad? seems kinda standard to me but there are arguments for not doing it.

call or fold now?

villain is ontilt34... i dont really have any reads on him, seems semi competent though