Yes not all women ovulate based off of the 28 day calculation....I actually ovulated a week later..which made me a week behind the pregnancy calculator
Only way to know for sure is an ultrasound
Yes I thought I was 7 wks almost 8 and I was barely 5. I agree get an ultrasound done to confirm.
If that was the date of your last period you would be 8 weeks 3 days pregnant. Even if you are less a ultrasound will show something as early as 5 weeks. I seen your post earlier about the ultrasound you had with an empty sack and your hcg not doubling..I'm sorry but just try to stay positive and get your hcg checked again in a few more days. Good luck!