hi
with dc1 and dc2 they started it from the first day of your last menstrual period. i was kind of banking this time around on being more pregnant than the nhs due date calculator thinks i am (because then i could feel good about not feeling so sick, whereas if i am only 4 weeks as said calculator thinks then of course i wouldn't be sick yet). this is the only explanation i can think of, especially as i know this many days past my last due date the calculators before definitely had me as more pregnant iyswim.
any ideas?