Eh sayang, back pain tu memang common dekat trimester ketiga especially bila dah 38 weeks, tapi kalau tu plus contractions atau discharge yang aneh, bolehlah jadi signs of labour, tapi honestly, back pain alone boleh jadi just dari baby pressure aje. Kang try paracetamol, warm compress, atau adjust sleeping position pakai pillow support, tapi I'd say check with your doctor or midwife kang to be safe lah, especially since you're so close to due date, better to confirm dah berapa cm dilated ke atau apa, daripada worry sendiri; a few of my mum friends yang sakit punggung masa itu rupa-rupanya just braxton hicks pun ada! Hang in there, dah tinggal sikit je!