Dilating

Sa

I had my weekly appointment today and I’m already dilated to a 3 and 50% effaced at 35 weeks 2 days. My OB also said baby is really low. I had my Weekly BPP ultrasound and NST and everything looks good. She weighs 5lbs 14oz. My question is has anyone delivered early and baby not need any extra support? And how long were u dilating before going into labor? I’m nervous and just want her to stay in until at least 37 weeks.

Also I was checked last week and wasn’t dilated at all, so it seems like its happening pretty fast..