Due date confusion!

Alison • Happily married, SAHM, 3yr old son, expecting a daughter in Nov.
So I know due dates are just an estimate but, I'm just a little confused about my dates. So If I went by my LMP, (02/05/15) id be due Nov 12. But when I went to the doctor at the beginning of my pregnancy they said I was due Nov 22. Which would put me at 35w2d. But the doctor said I was 35w4d today. So does that mean I'm due Nov 20?