Ultrasounds

Has anyone’s ultrasounds measured your having a small baby but it came out big? My oldest daughter was 9lb 14.5oz at birth I was 10lb 9oz at birth. I’m pregnant with my 2nd and she was measuring 2 days ahead I just got a 37 week growth scan and she’s suddenly measuring 36 weeks and her belly is bigger then her head. I’m scared. They brought up a C-section but I told them I want to try vaginally. I don’t think I’m having a big baby but has anyone experienced this