QQ with confusing action

[jmn32]

Villain has stats of 75/5/1.5 and is playing very poorly.


PokerStars 0.50/1.00 Hold'em (10 handed) converter

Preflop: Hero is MP2 with Q[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">2 folds</font>, UTG+2 calls, MP1 calls, <font color="#CC3333">Hero raises</font>, <font color="#666666">1 fold</font>, CO calls, <font color="#666666">1 fold</font>, SB calls, BB calls, UTG+2 calls, MP1 calls.

Flop: (12 SB) 4[img]/images/graemlins/spade.gif[/img], 8[img]/images/graemlins/heart.gif[/img], 3[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(6 players)</font>
SB checks, BB checks, UTG+2 checks, MP1 checks, <font color="#CC3333">Hero bets</font>, CO calls, SB folds, BB calls, UTG+2 calls, MP1 folds.

Turn: (8 BB) 4[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
BB checks, UTG+2 checks, <font color="#CC3333">Hero bets</font>, CO folds, BB folds, UTG+2 calls.

River: (10 BB) 5[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">UTG+2 bets</font>, Hero ???


Where has that bet come from? Now obviously I'm not folding, but is a raise correct and if so what do I do if 3-bet?