Serious question mammas. For the mammas who's been pregnant early after giving birth with no period…

Serious question mammas.

For the mammas who's been pregnant early after giving birth with no period because of breastfeeding, have you ever went to the doctors and not knew how far along you was so you had a vaginal ultrasound and they seen no sac in the uterus; did one appear a few weeks later or was it a tubal pregnancy or a chemical pregnancy!?

At the docs today they didn't see a sac but the test said I was pregnant as this is the 5th test now . I tested over the weekend and was still pregnant. They drew my blood today and I'm going back Wednesday for the second draw. Just curious how everything turned out. Never had this happen before and before my last son I had one miscarriage and one chemical. So I'm super nervous. I was also told I could be super early as a test can detect as little as 3 weeks. So I could be 4 weeks. .