First abdominal ultra sound 6 weeks 3 days

So I had my first ultra sound at six weeks and 3 days. The doctor found the sac and said everything looked fine and to come back in 2 weeks, once she finds the heartbeat she will run the blood work. Well after reading so many post of woman hearing the heart beat at 6 weeks I freaked. I love my doctor because she understood my concern and agreed to see me again Friday, I will be 6 weeks and 6 days, she did say I measured 2 days smaller but I may have ovulated later, not to worry my results were normal. Anyone else have a similar situation?