i run good but run into a tough spot

another good day yesterday at 50nl. i am up over 13 buy-ins in 4 days. i run good but also have been playing well. i've been managing to get lots of value from my big hands - which occassionaly means i get stacked myself - and i've been getting paid off. after running bad for over a month, i am enjoying my poker. i guess i have tightened up a bit too - which is not a bad idea when you are running bad and one which i have heard green plastic suggest. (there's a good interview with green plastic at liquidpoker)

i'll look up some hands from yesterday's online session and post them later.

i went to the fortune rooms in bangor last night. they do a tourney's most nights of the week but i only really go on a friday night. there is usually a field of 60 or so. here was the toughest hand i had to play last night:
final table, 9 left. I have 66k, blinds are 3/6 (prob about 5th in chips)
i am in BB with J3h, everyone folds to sb who limps. (sb has me covered but doesnt seem very good) i think about raising then decide to see a flop. flop comes down Ah Qh Jc
sb checks and i bet 6k
sb check raises me to 18k
if i call i have 42k behind. we are virtually on the bubble.
i think this is a particularly tough spot. what range of hands do you put him on and what is your move and why? (also posted this here on 2+2)