Stupid check?

[Poker_Ink]

Party 1/2 (6 max) 6 handed. MP is very loose and aggressive. No reads on any of the other players. I flat called the turn raise becasue I wanted to check-raise the river. Is this too cute, or a good line?

I am UTG with Q [img]/images/graemlins/heart.gif[/img]Q [img]/images/graemlins/spade.gif[/img]
I raise, MP calls, Button calls, both blinds call.

Flop comes: Q [img]/images/graemlins/club.gif[/img]8 [img]/images/graemlins/club.gif[/img]9 [img]/images/graemlins/diamond.gif[/img]
SB bets, BB calls, I raise, MP calls, button calls, both blinds call.

Turn comes: Q [img]/images/graemlins/diamond.gif[/img]
SB checks, BB checks, I bet, MP raises, button calls, both blinds call, <font color="red"> I flat call </font>

River comes: Js
SB checks, BB checks, <font color="red"> I check
</font>

So, was this dumb, and should I have just pounded the turn and bet the river?