Due date?

So I go to my first prenatal appointment today and got my first ultrasound. The doctor said that I conceived around February 12th 2017 and she said based on my ultrasound, it indicates I'm 9 weeks and 4 days along. But nurture glow indicates that I'm only 7 weeks along. How can I change that on my profile because it will not let me. Can anybody help me with this? Thanks in advance Melissa