Currently 5.20am

Hello I’m 38 weeks today (due 2nd April) I live in the uk it’s currently 5.20am and I’ve been asleep since 12 I just been woken up by a dull back ache in the side of my left lower back. I’ve never had this pain before and I’ve never had it where I’ve been woken up by pain. Does anyone know why this is happening? Could I be going into labour soon?