How bad was this play?

[Tilted Litt]

Party Poker No-Limit Hold'em, $0.50 BB (10 handed) converter

UTG ($30.70)
UTG+1 ($24.50)
UTG+2 ($53.50)
MP1 ($24)
MP2 ($6.75)
MP3 ($25)
CO ($19.45)
Hero ($35.30)
SB ($31.50)
BB ($21.70)

Preflop: Hero is Button with A[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/club.gif[/img].
UTG folds, UTG+1 raises to $4, UTG+2 folds, MP1 folds, MP2 folds, MP3 folds, CO folds, Hero raises to $7.5, SB folds, BB folds, UTG+1 calls $3.50.

Flop: ($15.75) 3[img]/images/graemlins/heart.gif[/img], Q[img]/images/graemlins/spade.gif[/img], J[img]/images/graemlins/diamond.gif[/img] <font color="blue">(2 players) </font>
UTG+1 bets $17 (All-In), Hero calls $17.

Turn: ($49.75) 9[img]/images/graemlins/spade.gif[/img] <font color="blue">(2 players, 1 all-in) </font>

River: ($49.75) K[img]/images/graemlins/diamond.gif[/img] <font color="blue">(2 players, 1 all-in) </font>

Final Pot: $49.75
<font color="#990066">Main Pot: $49.75, between UTG+1 and Hero.</font> &gt; <font color="white">Pot won by Hero ($49.75).</font>

Results in white below: <font color="white">
UTG+1 shows 6c 6d (one pair, sixes).
Hero shows Ad Kc (one pair, kings).
Outcome: Hero wins $49.75. </font>

At the flop I put my oppenent on a bluff or at worst a QX or JX. So I figured I had at worst 10 outs w/ my straight and pair draws.