Perfect slowplay?

[Poldi]

SB is 49/13/0.8 (more AF on turn + river)
Button is 63/12/0.77. weak player who is calling a lot.


Party Poker 1/2 Hold'em (6 max, 6 handed) converter (http://www.selachian.com/tools/bisonconverter/hhconverter.cgi)

Preflop: Hero is BB with A/images/graemlins/heart.gif, 3/images/graemlins/heart.gif.
<font color="#666666">1 fold</font>, MP calls, CO calls, Button calls, SB completes, Hero checks.

Flop: (5 SB) 3/images/graemlins/diamond.gif, 3/images/graemlins/club.gif, 8/images/graemlins/spade.gif <font color="#0000FF">(5 players)</font>
<font color="#CC3333">SB bets</font>, Hero calls, MP folds, CO folds, Button calls.

Turn: (4 BB) 6/images/graemlins/heart.gif <font color="#0000FF">(3 players)</font>
<font color="#CC3333">SB bets</font>, Hero calls, Button calls.

River: (7 BB) 7/images/graemlins/heart.gif <font color="#0000FF">(3 players)</font>
<font color="#CC3333">SB bets</font>, <font color="#CC3333">Hero raises</font>, Button folds, SB calls.

Final Pot: 11 BB

My position relative to the bettor sucks on the flop. Pot is small so I dont want to shut everyone out as most probably are drawing very thin.
Pretty much the same situation on the turn although very unlikely backdoor straight draws might now be drawing live.
River is a bit scary but SB would not bet a draw on the turn, Button might even have called with A-high so far.
I am pretty sure SB will call my raise on the river and I am ahead almost always. Chance for button to overcall would be like 50%.

Was it the right time to slowplay (even the turn)?