NLCASH 0.5/1 how badly did I butcher this hand

[TNixon]

Bought in for $40 against somebody sitting with $20 at a .5/1 NL table.

This is about the 13th hand of the session without any showdowns. The only thing I know about this player is that he's not overly aggressive preflop (he's been respecting my preflop raises, and has folded a few buttons), and that he seems to want to be every time he's checked to.

Full Tilt Poker
No Limit Holdem Ring game
Blinds: $0.50/$1
2 players
Converter

Pre-flop: (2 players) Hero is BB with 7[img]/images/graemlins/spade.gif[/img] A[img]/images/graemlins/diamond.gif[/img]
SB calls, Hero checks.

Flop: 3[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/club.gif[/img] 4[img]/images/graemlins/heart.gif[/img] ($2, 2 players)
Hero checks, <font color="#cc0000">SB bets $2</font>, <font color="#cc0000">Hero raises to $5.25</font>, SB calls.

Turn: 5[img]/images/graemlins/heart.gif[/img] ($12.5, 2 players)
Hero checks, <font color="#cc0000">SB bets $9</font>, Hero calls.

River: 7[img]/images/graemlins/club.gif[/img] ($30.5, 2 players)
Hero checks, <font color="#cc0000">SB bets $5</font>, Hero calls.

Results:
Final pot: $40.5
<font color="#ffffff">SB showed 3s 6d</font>
<font color="#ffffff">Hero mucks 7s Ad</font>