Dialated Already

diana • Mother to a wonder 1 year old and Due with #2 Nov 30th.
I'm be 37 weeks on Saturday . My 1st check at 35 weeks and 4 days I was 2 1/2 cm and 75% effaced . My 2nd check up today I'm 3 1/2 cm and 80 % . Dr is hoping for another week if not 2 but after my check today I've been having horrible contractions . I've been trying to rest and take it easy . I don't want to have him too early but then again I'm in so much pain I just want him here already . I never dialated pass 2cm with my daughter and didn't really have any contractions until after my water broke @ 39 weeks and 2 days . Anyone else dialated early ? How long after you dialated did you have your baby ?