Folding second Nutz

This hand came up during a $2 $4 no limit holden game id been playing for about three hours and well up in front of me i had over 1k i look down and pick up pocket nines,just double the blind and get four callers.
Flops comes out 2-J-9 rainbow short stack in first position goes all in for 20 bucks i flat call next guy reraises 20 more and the guy on the button call the 40 now back to me 20 more i decide to take it down now and reraise another 100 the original raiser folds and guy on button all in for 800 dollars.Very confused with all the action thinking someone else must have had a Jack but then knowing the guy was pretty tight i fold.I see his cards anyway as the first guy was all in he had A-2 and just as i thought trip Jacks.Last card i would have hit quads,gutted i was.