about the due date

Hi ,
I went to consult my doctor for the pregnancy check up after my first ultra sound scan.In the scanning result the pregnancy is confirmed for 7weeks &2days & my DD is mentioned as 03/04/11(my LMP 28/06/10).But the doctor said my due date will be  05/02/11..!! I got wondered on what basis she'd have calculated the due date.Is that a mistake from the doctor side or is there any other things she'd have in her mind for DD calculation???
maria

[AnnieBrooke]

The British way of doing dates as numbers is different than the U.S. way, so here is what I think you are saying:  
Your due date mentioned by the ultrasonographer is April 3rd (2011)
Your last menstrual period began June 28, 2010
The doctor said your due date is February 2nd (2011)

Is that right?  (In the U.S., we read 05/02/11 as May 2nd.)  

Anyway,  I would go by the dates the ultrasonographer gave, since that is usually an instant calculation done by the computer on their machine.  Doctors can have other things on their minds, and often calculate manually.  But that said, it is certainly worth asking the doctor about the discrepancy.