6 Wks 5 days from last period measuring....

Jen
So the date of my last period was August 5th... Should be 6 weeks 5 days...They did a vaginal ultrasound today and I'm measuring 6 weeks exactly.. Told me my due date is May 17th.. Anyone else a few days off ? Why is this ?? Late ovulation ?? I'm Ok though...we saw the heart beat flickering and heart beat measured 116 and mine was 110.. Any ladies care to comment. Thanks