Nervous wreck ! No heartbeat !

I am measuring 5 weeks 6 days today . I went in for a vaginal ultra sound and my levels have been checked all week and risin well ! They saw a gestational sac and healthy yolk sac but no baby or heartbeat . I’m so scared but she said this is totally normal and not to worry it can change in the matter of days . With my last baby I saw the heart beat at 5 weeks 5 days . I have to wait for the doctor to call me to go over results and then schedule a follow up . Did anyone have this problem and been okay ? The tech kept reassuring me that the yolk sac was a good sign !