NL400 hand vs an unkown

[MarkL444]

5 handed 2/4 blinds
two players fold and i raise to $12 with Q [img]/images/graemlins/heart.gif[/img]9 [img]/images/graemlins/spade.gif[/img] on the button. the SB calls. he is new to the table so i dont have any read on him. he has just under $400, i have him covered. the BB folds

flop is Q [img]/images/graemlins/diamond.gif[/img]9 [img]/images/graemlins/diamond.gif[/img]2 [img]/images/graemlins/club.gif[/img] pot is ~$26

sb checks, i bet 18, he min check raises me to 36. i make it $80 to go, he calls without really hesitating.

Turn is A [img]/images/graemlins/heart.gif[/img] pot is ~$185

he bets $125

thoughts?