cant keep track of weeks

[soconfused]

this is something that has been confusing me for a while now. when i had a scan at 25weeks the widwife told me the due date would be 13/08/05. although when i made my counter and entered this date it makes me 26weeks and 4 days today. although when i saw the midwife this morning she said that today was the beginning of weeks27 so i had reached the 3rd trimester. i know its only a few days difference but im wondering how accurate this is and if it would be the midwife giving me a false due date or if she had just miscalcutated on the spin the wheel chart thing that she used?
do you think i should change the counter so i have the right amunt of days as the midwife says or just go with the counter?

 

[AmberNicole]

I would go by what your midwife is using just because that's what's on file. My ultrasound at 19 weeks 3 days, put me 4 days behind to 18 weeks 6 days but my midwife is going by my original due date still.