Did I play this straight-flush draw too fast?

[Pharcyde]

This guy's 50/8.3/.58 over 12 hands. My plan on the flop was to check-raise with the hopes of getting it HU, or to just see a free turn. When he overbet the pot I put him on at least TPGK, probably 2-pair, maybe a set of sevens or nines. Should I have been worried about his 3-bet, or happy to get it in on the flop?

PokerStars No-Limit Hold'em, $0.10 BB (6 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

saw flop|<font color="#C00000">saw showdown</font>

UTG ($10)
<font color="#C00000">MP ($9.65)</font>
CO ($18.40)
Button ($3.95)
<font color="#C00000">Hero ($12.35)</font>
BB ($9.90)

Preflop: Hero is SB with 8[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/heart.gif[/img].
UTG calls $0.10, MP calls $0.10, <font color="#666666">1 fold</font>, Button calls $0.10, Hero completes, BB checks.

Flop: ($0.50) 9[img]/images/graemlins/heart.gif[/img], J[img]/images/graemlins/diamond.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(5 players)</font>
Hero checks, BB checks, UTG checks, <font color="#CC3333">MP bets $1</font>, Button folds, <font color="#CC3333">Hero raises to $3.5</font>, BB folds, UTG folds, <font color="#CC3333">MP raises to $7</font>, <font color="#CC3333">Hero raises to $10.5</font>, MP calls $2.55 (All-In).