Hey I know it’s hard but don’t get too worried now. I’m also a FTM, went for 1st scan thinking I’m 6 weeks but also only saw gestational sac and only saw fetal pole and detected heartbeat on the following week. It turned out I just turned 6 weeks then! Counting your gestational term using last menstrual period is not the most accurate, just need to wait it out more give it time to grow and develop
Kris G