sensing weakness

[phifediggy]

6-handed 5/10 NL live, hero has been playing pretty loose preflop. opponents have been pretty tight and moderately aggressive.

relevant stack sizes:
hero $1200
SB $800
UTG $1000

UTG and MP both limp, hero calls in CO with 7[img]/images/graemlins/club.gif[/img] 6[img]/images/graemlins/diamond.gif[/img], button folds, SB raises to $35, BB folds, UTG and MP call, hero calls.

flop Q[img]/images/graemlins/heart.gif[/img] 8[img]/images/graemlins/spade.gif[/img] 5[img]/images/graemlins/heart.gif[/img]
SB bets $45, UTG doubles the bet to $90, hero calls, SB calls. at this point i'm putting SB on top pair and UTG on a flush draw.

turn is an 8[img]/images/graemlins/club.gif[/img]
SB checks, UTG checks, hero bets $250. thoughts?