When did you all start dilating? I went for my first check last week and I'm not dilating at all. Dr…

When did you all start dilating? I went for my first check last week and I'm not dilating at all. Dr also said that I have a narrow birth canal and she doesn't think I will be able to birth anything bigger than 7-7.5 lbs. she's not one to induce or schedule sections unless medically necessary. She scheduled me an extra ultrasound on the 20th to check his size and position. I'm so nervous now!