I'm 39 weeks. And last night as I was sleeping I started getting sharp cramping pains down the lower part of my belly. It felt like menstrual cramps but very bad ones. And I was also get lower back pains. They simply came and went every 3-4 minutes for only about 30-40secs. I also felt some tightness in my belly but like towards the upper part, I also felt like I had poop but couldnt. Is this normal?? Was I have contractions? Help please I'm worried, should I go to the hospital next time or is this all normal for labor?