Dilating and pelvic pain

Lately I've been feeling like I'm already dilating I'm ask my doctor in a few weeks at my next appointment. I wouldn't know cuz I never dilated with my first. But anyways I've been also having like lower back pain and my whole pelvic area. Idk if I should be worry. Preterm labor idk I'm nervous. My first had no issues like this but she was early at 37 but I'm barely at 27 weeks right now. I would see my doctor early but I have wait till April 1 cuz I had to switch plans for my doctor.