Top pair ace w/ gutshot in unraised pot

[Stalrock]

Villain was 21, 5, 1.1

Is there even a reason to call the flop raise? I mean if and when I hit my straight, it will slow my opponent down. As played, what do you think about my turn play? Should I check raise that eventhough the heart came?

Poker Stars, $0.50/$1 NL Hold'em Cash Game, 5 Players
LegoPoker Hand History Converter

UTG: $28.70
CO: $219.30
BTN: $123.20
Hero (SB): $101.50
BB: $95.80

Pre-Flop: 5[img]/images/graemlins/spade.gif[/img] A[img]/images/graemlins/spade.gif[/img] dealt to Hero (SB)
UTG folds, CO calls $1, BTN folds, Hero calls $0.50, BB checks

Flop: ($3) 3[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/heart.gif[/img] 4[img]/images/graemlins/heart.gif[/img] (3 Players)
<font color="red">Hero bets $3</font>, BB folds, <font color="red">CO raises to $9</font>, Hero calls $6

Turn: ($21) 2[img]/images/graemlins/heart.gif[/img] (2 Players)
Hero checks, <font color="red">CO bets $10</font>, Hero calls $10

River: ($41) 2[img]/images/graemlins/spade.gif[/img] (2 Players)
Hero checks, <font color="red">CO bets $20</font>, Hero calls $20