I had a vagina ultrasound today but the doctor got called to a delivery so a new np had to do it and she had me measuring at 6 weeks, heart rate was 121, I went 10 days ago and the doctor did my sono but there was just a sac and said it was a healthy sac measuring 5 weeks 3 days.... I only had intercourse once which was December 4th of 2020 of course. Could she be wrong? That would put me a whole week behind then what I would be which would be 7 weeks today. Has this happened to anyone what was the outcome? Thank you all in advance!