Can this be labor?

judy👶💕 • Pregnant with a baby girl, lost my baby boy preterm at 24 weeks two years ago. Staying positive! ❤️😊
Woke up with this huge cramp like pain around 430. Been havig them irregular ever since.. They range from 8 or 5 to 3 and 3 minutes. And last from 1 minute to 1 and a half..I have lower back pain that won't go away. At first I thought it was constipation but I tried going and nothing. I'm drinking water and laying down on sides and doesn't seem to help. 
Can this be it? Or do I wait longer?
Oh and I'm 39 weeks and 2 days!