A Two Pair Hand

[JARID]

PP 50+5 tourney.

BB = t150
Hero 4500
SB 6700

I am dealt J9 [img]/images/graemlins/heart.gif[/img] on the button.
Its folded to me and I open to t450. This is a new table, so there are no reads.

SB calls and the BB folds. Pot = t1050

Flop: J [img]/images/graemlins/club.gif[/img]T [img]/images/graemlins/heart.gif[/img]9 [img]/images/graemlins/club.gif[/img]

SB checks, hero bets t750, sb check raises to t1500, hero ??

Your move and why?

Thanks-
Jarid