small flush on paired board

I have only been playing a couple of orbits and have no reads except that MP and Button have both been involved in almost every hand. Mostly curious to hear comments on turn play. Should I have led? Should I be willing to go broke on this paired board?

Party Poker No-Limit Hold'em, $ Hero (6 max, 5 handed) converter

MP ($22.84)
Button ($68.79)
SB ($18.35)
Hero ($28.75)
UTG ($23)

Preflop: Hero is BB with 7[img]/images/graemlins/club.gif[/img], 6[img]/images/graemlins/club.gif[/img]. SB posts a blind of $0.10.
<font color="#666666">1 fold</font>, <font color="#CC3333">MP raises to $1</font>, Button calls $1, SB (poster) calls $0.90, Hero calls $0.75.

Flop: ($4) K[img]/images/graemlins/club.gif[/img], 9[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, Hero checks, <font color="#CC3333">MP bets $1</font>, <font color="#CC3333">Button raises to $2</font>, SB calls $2, Hero calls $2, MP calls $1.

Turn: ($12) A[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(4 players)</font>
SB checks, Hero checks, MP checks, <font color="#CC3333">Button bets $4</font>, SB folds, <font color="#CC3333">Hero raises to $12</font>, MP folds, Button calls $8.

River: ($36) K[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets $15</font>, Hero folds.

Final Pot: $51