Girls, hello. I'm having some trouble today after my ultrasound. My ge…

Girls, hello. I'm having some trouble today after my ultrasound. My gestational age is 7 weeks, but the ultrasound said that the embryo is only 4 weeks old at 0.72 mm. It didn't see the embryo properly. The sonographer is very young and may not be very experienced, so I suspect it could be a missed miscarriage. Tomorrow I will go for another blood test to check HCG levels (I had it done 3 days ago, it seemed to match the expected period). I don't have any pain anywhere, just a little breast tenderness, heartburn (everything else like during pregnancy). I want to do another ultrasound, is it harmful to do it often? On Monday