Doctors are stupid at my office

They won't change my due date (which is currently April 19) but because of how big he is they are saying I could have him as soon as March 19 and he might be Full term and even though I have extra fluid around him (twice as much as I should) I have talked to other moms that have been told this and they were put on bed rest and checked by ultrasound at least every week or two none of this did they tell me they told me that that was my last ultrasound should I change drs I'm a ftm 35 weeks along