hello there, just sharing my experience.. the same happened to me.. i scheduled my first appt on what I thought was 5 weeks based on my last menstrual period but when the doctor scanned me vaginally, he couldn't really see anything.. except a very small dot which he can't even confirm. Of course, I was feeling worried because I thought there would at least be a visible gestational sac detected.. it didn't help when I was also experiencing cramps which made me thought that it might be an ectopic pregnancy. (hence not detected in the uterus or sth) The doctor prescribed me duphaston and asked me to come back 2 weeks later as it might be too early. When I went in again 2 weeks later, we could detect the baby and heartbeat and the scan measured at 6 weeks and 2 days. The last menstrual period dating of gestational age may not be the most accurate as ovulation could also take place later than we thought. Though its easier said than done, I would say try not to worry too much.. it would just be too early!! Rest well and stay happy mommy, hope all goes well for you in the next appointment.
might be a bit early, development probably a bit later. hve faith
Cheryl Tan