SB v BB Hand

Middle of the stars 180 sng (~90 people left). I'm sitting with 6500 (around 20th place). I have been picking my spots to pick up blinds and I am chip leader at the table. the table has been rather tight as well. I have also slow-played a couple of monster hands recently and picked up some big pots in the showdown. Blinds are 30-60.
Hero has Q [img]/images/graemlins/diamond.gif[/img]8 [img]/images/graemlins/diamond.gif[/img] in SB
Folded to SB
BB has ~4000 and has been quite tight
I decide to call (a mistake, i know, i thought about raising and trying to take it down, but i thought i could take it down on the flop)
BB checks
flop comes Q [img]/images/graemlins/heart.gif[/img] 9 [img]/images/graemlins/heart.gif[/img] 4 [img]/images/graemlins/club.gif[/img]
i check
BB bets 100
I bet 450
BB calls
turn comes J [img]/images/graemlins/diamond.gif[/img]
I bet 675
BB goes all in
What do you do here?
Comments on any other street would be helpful
Results in white:
<font color="white">
I call
He has K hearts 4 hearts
River comes a 4 and im down to ~2500 </font>