Constant lower ab pain 39 weeks

I turned 39 weeks today. I woke up at 1 a.m. needing to use bathroom and having pelvic discomfort. After using restroom it turned to pelvic pain. Then I felt the sudden urge to vomit. Now I’m laying on the couch with a pillow hugged against my lower abdomen. The pain is constant, not coming and going. I took Tylenol hoping it would help, but it’s been about an hour and no relief. Any ideas what’s going on?