Cervical dilation pain?

Unknown

I'm 33 weeks and 3 days. I'm on pelvic rest because my son is 'engaged' and completely in my birth canal according to my midwife and I'm 1 cm dilated and 50 effaced. Well today and a couple times every day just about, I get painful menstrual like cramps that will come and go but today they were really painful, also with bad nausea. Also a lottttt of rectal and pelvic pressure. And I've had these dilation pains for weeks and weeks now but today they are stronger and almost painful. They're pretty bad. It's like someone I forcing my cervix open and it really hurts. And it is happening constantly not just every now and then. Any ideas what it is?? And since my cramps aren't really regular and close together do I need to go to LD or would it be fine to just put in a call to my obgyn office tomorrow