Ultrasound dates

Rebecca

Hi Ladies,

I had my first ultrasound last Thursday when I was 9w2d (going my the first day of my last period). However, I was told I was a week behind so 8w2d (late ovulation or something). I’m just wondering today should I be going by 10w1d or 9w1d? I’m so confused. First pregnancy so I haven’t a clue!