NL 100 Laying down top pair on a 3-flush flop

[rjacobs003]

Sounds ok from the title but any thoughts on this play. Have no reads on the villian. He's been at the table or 5 hands and seems aggressive.

PokerStars No-Limit Hold'em, $1.00 BB (9 handed) internettexasholdem.com

Hero ($153.55)
UTG+1 ($99)
MP1 ($20.50)
MP2 ($19.50)
MP3 ($107.10)
CO ($46.90)
Button ($14.20)
SB ($107.60)
BB ($87.80)

Preflop: Hero is UTG with Q[img]/images/graemlins/spade.gif[/img], K[img]/images/graemlins/diamond.gif[/img].
Hero calls $1, <font color="#666666">3 folds</font>, MP3 calls $1, <font color="#666666">2 folds</font>, <font color="#CC3333">SB raises to $4</font>, <font color="#666666">1 fold</font>, Hero calls $3, MP3 folds.

Flop: ($10) J[img]/images/graemlins/heart.gif[/img], K[img]/images/graemlins/heart.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">SB bets $6</font>, <font color="#CC3333">Hero raises to $15.5</font>, <font color="#CC3333">SB raises to $30</font>, Hero folds.

Final Pot: $55.50