No heartbeat no baby

So today I had my very first ultrasound I was assuming that I was going on 9 weeks pregnant and all they found was a gestational sack measuring at 6 weeks I ended up getting a second opinion at the Er because the lady did not seem sure of herself that did the first ultrasound. However the ultrasound at the hospital showed a gestational sack repacking at 7 weeks 1 day still no baby still no heartbeat my HCG levels were at 29,450 when my OBGYN called this morning . Should I be worried ? Or is it possible baby will show up hospital said that baby should show up because I have no bleeding, abdominal pain , ect however I can’t help but worry and would just like to know if any other mommas have experienced this ? Tia