Due date


Has anyone else’s doctor not changed there due date based on the ultrasound scans? Back story, when I originally went in I thought I was at 9 weeks based on my last period, but the tech said I was measuring 7w3d, fast forward to the 20 week and she was measuring 5 days ahead. My doctor said that one of the ultrasounds is probably wrong and they want to do their own. So had the doctor due an ultrasound at 32 weeks and it had her measuring 8 days ahead, but my doctor is still leaving the original due date even though they say she is big for her to be due then. Thoughts?