$55: Standard small overpair, take 2

[Taraz]

I can never decide what to do in this spot if I don't have any good reads.

Level 2 (15/30)
Hero (t1040)
Button (t2027)
SB (t1525)
BB (t530)
UTG (t1438)
UTG+1 (t915)
MP1 (t1070)
MP2 (t680)
MP3 (t775)

Preflop: Hero is CO with T[img]/images/graemlins/club.gif[/img], T[img]/images/graemlins/diamond.gif[/img].
4 folds, MP3 raises to t90, Hero calls t90, Button calls t90, 2 folds.

Flop: (t315) 5[img]/images/graemlins/spade.gif[/img], 9[img]/images/graemlins/heart.gif[/img], 4[img]/images/graemlins/heart.gif[/img] (3 players)
<font color="red">MP3 bets t225 </font> , Hero???