AKo is costing me

[colehard]

Not sure if the 25NL are too micro for anyone to care about. Any advice on this hand would be good as AKo is one of my big losers. Mostly it appears to good luck on the opponent's part (flushes, pocket aces etc.) However I am trying to migrate from tournies and limit to NoLimit. Do I have to pay off the possible flush or would a turn bet have told me all I needed to know?

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

BB ($23.99)
UTG ($14.58)
Hero ($25.89)
Button ($11.15)
SB ($39.75)

Preflop: Hero is MP with K[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/spade.gif[/img]. SB posts a blind of $0.1.
UTG calls $0.25, <font color="#CC3333">Hero raises to $1</font>, Button calls $1, <font color="#666666">2 folds</font>, UTG calls $0.75.

Flop: ($3.35) Q[img]/images/graemlins/heart.gif[/img], A[img]/images/graemlins/heart.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">UTG bets $2</font>, <font color="#CC3333">Hero raises to $4</font>, Button folds, UTG calls $2.

Turn: ($11.35) 3[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
UTG checks, Hero checks.

River: ($11.35) 3[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">UTG bets $5</font>, Hero calls $5.

Final Pot: $21.35