KK vs flopped pair

[crownjules]

This has been my luck as of late. Making almost no draws, good hands getting beat by four flush cards hitting the board (and I never happen to have one of the flush cards in my hand). Being down 100BB kinda sucks right now, but I keep telling myself the cards will start coming eventually. Anyway...

The villain was new to the table, so no reads.

Party Poker 0.5/1 Hold'em (9 handed)

Preflop: Hero is MP2 with K[img]/images/graemlins/club.gif[/img], K[img]/images/graemlins/spade.gif[/img]. MP3 posts a blind of $0.5.
<font color="666666">3 folds</font>, <font color="CC3333">Hero raises</font>, MP3 (poster) calls, <font color="666666">1 fold</font>, Button calls, <font color="666666">1 fold</font>, BB calls.

Flop: (8.50 SB) 3[img]/images/graemlins/diamond.gif[/img], 3[img]/images/graemlins/heart.gif[/img], 2[img]/images/graemlins/diamond.gif[/img] <font color="blue">(4 players)</font>
BB checks, <font color="CC3333">Hero bets</font>, <font color="CC3333">MP3 raises</font>, Button calls, BB folds, Hero calls.

Turn: (7.25 BB) Q[img]/images/graemlins/spade.gif[/img] <font color="blue">(3 players)</font>
<font color="CC3333">Hero bets</font>, <font color="CC3333">MP3 raises</font>, Button folds, Hero calls.

Check/call here?

River: (11.25 BB) 3[img]/images/graemlins/spade.gif[/img] <font color="blue">(2 players)</font>
<font color="CC3333">Hero bets</font>, <font color="CC3333">MP3 raises</font>, Hero calls.

With trip 3s, I thought he had tried bluffing me with the threat of trip 3s and bet into him and called his reraise. Wrong thought/move?

Final Pot: 15.25 BB

Results in white below: <font color="white">
Hero has Kc Ks (full house, threes full of kings).
MP3 has 2s 3c (four of a kind, threes).
Outcome: MP3 wins 15.25 BB. </font>