Need opinion asap!

WARNING: (TmI) ...In 29+5 wks, and for the past 2nights i wake up in the middle of the night with my panties wet but not sure if it was just urine frm the baby pushing down or my constant bathroom trips. But last night my panties and vagina was wet so i go to bathroom to pee and clean myself and try not to worry... anyway, today i was standing and all of a sudden i feel liquid come out right after a small braxton hick/contraction... im scared and not sure if im going into pre term labor. Ever since, my lower back is killing me and i cant hold my bowel movements...