raised on river oop-what to do?

[RED FACE]

Villain is MP2, 42/14 after too few hands.

No-Limit Hold'em, $ BB (10 handed) FTR converter on zerodivide.cx

UTG ($36.30)
UTG+1 ($97.30)
UTG+2 ($97.51)
Hero ($100)
MP2 ($98.82)
MP3 ($118.14)
CO ($122.25)
Button ($103.40)
SB ($21.13)
BB ($120.50)

Preflop: Hero is MP1 with 4[img]/images/graemlins/club.gif[/img], 4[img]/images/graemlins/diamond.gif[/img]. SB posts a blind of $0.50.
<font color="#666666">3 folds</font>, Hero calls $1, MP2 calls $1, <font color="#666666">3 folds</font>, SB (poster) completes, BB checks.

Flop: ($4) Q[img]/images/graemlins/spade.gif[/img], 2[img]/images/graemlins/spade.gif[/img], 9[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, BB checks, Hero checks, MP2 checks.

Turn: ($4) 4[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, BB checks, <font color="#CC3333">Hero bets $3.5</font>, MP2 calls $3.50, SB folds, BB folds.

River: ($11) 8[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets $6</font>, <font color="#CC3333">MP2 raises to $20</font>.

The hands I fear are TJ or 2 spades having sp'ed the turn.