Help. Baby growth

Tytiannai

I’m 35w1d... overall I’ve had about 7 different due dates so I’m no longer concerned about my sons arrival. He just gets here when he gets here. But every time i go to the doctor they come up with a different number yet my baby is always measuring from pubic bone about 3/4 weeks ahead. Im measuring at 38 weeks currently... but only 35, yet they want me to come back in two weeks for another ultra bc they want to make sure he’s growing properly? He already weighs 6 lbs... has anyone ever heard or had any of these problems? I’m 5ft 1 his dad is 6’1... maybe he has my height and they just don’t have the right measurements? Idk I’m just confused about everything 😩😩😩