Did I play my A-8s correctly?

PokerStars No-Limit Hold'em, $0.10 BB (6 handed) FTR converter on zerodivide.cx (http://www.zerodivide.cx/converter)

Button ($2.85)
SB ($14.85)
BB ($3.55)
UTG ($4)
Hero ($7.70)
CO ($4.40)

Preflop: Hero is MP with A/images/graemlins/spade.gif, 8/images/graemlins/spade.gif. UTG posts a blind of $0.10. CO posts a blind of $0.15.
[color=#CC3333]UTG (poster) raises to $0.2</font>, Hero calls $0.20, CO (poster) calls $0.10, Button calls $0.20, SB calls $0.15, BB calls $0.10.

Flop: ($1.25) K/images/graemlins/club.gif, 8/images/graemlins/diamond.gif, 8/images/graemlins/club.gif [color=#0000FF](6 players)</font>
SB checks, BB checks, UTG checks, [color=#CC3333]Hero bets $0.5</font>, CO folds, Button calls $0.50, SB calls $0.50, BB folds, UTG folds.

Turn: ($2.75) A/images/graemlins/club.gif [color=#0000FF](3 players)</font>
[color=#CC3333]SB bets $1</font>, [color=#CC3333]Hero raises to $2</font>, Button folds, SB calls $1.

River: ($6.75) K/images/graemlins/heart.gif [color=#0000FF](2 players)</font>
[color=#CC3333]SB bets $0.5</font>, [color=#CC3333]Hero raises to $4</font>, [color=#CC3333]SB raises to $7.5</font>, Hero calls $1 (All-In).

Final Pot: $19.25

[Jerkass333]

You should post this in small stakes nl forum, you'll get better responses as this is a limit forum. Also, I don't like the river raise.