What Does That Mean?? 38w 1d

FTM here.

Weekly checkup yesterday. I’m only 2cm dilated but doctor said, “oh! You’re almost completely thinned out.” Didn’t really talk with me any. Just told me had no idea when I’d have my baby. I obviously know that he doesn’t know but was wondering:

who all lasted until 40 weeks with completely thinned cervix?

I’m having very low pressure in my vagina and butt, pretty constant throughout the day. Back has definitely been hurting. Baby is moving around as normal.