This is hard to figure out! But first, congratulations!! Are you excited? I'm excited for you! Is this your first?
Anyway, So, you could have ovulated later than you normally do as in you had a really long cycle. This is how cycle's work-- day one of your period is cycle day one and it goes from there. You ovulate at the most common time, it would be around day 14 to 15. However, if you are having long cycle, you'd ovulate on a much later day in the cycle. Maybe day 20 or 30 or 40 or more. Then two and a half weeks after that, you normally get a positive pregnancy test. But it is hard to say exactly when you got pregnant because you weren't taking pregnancy tests the whole time through it sounds with a gap of a few weeks in between. does that make sense? Or you are one of those very rare women who doesn't get a positive right away when you are really pregnant. It's hard to know which one!!! I hope you can get squeezed in to see your doctor sooner. My doctor starts seeing ladies at 8 to 9 weeks pregnant and will not see them before that. I wonder if this is why your doc is waiting a bit to see you. But either way, this is exciting news!
Congratulations you could for a private early reassurance scan. Or wait for your 12 week dating scan at the hospital.