6 weeks 4 days

Hey guys, I’m 6weeks 4 days pregnant. I went to the hospital due to cramping but everything was fine, they did a abdominal ultrasound first with a Doppler, the nurse said he saw the number but didnt hear anything and he said the number was 180, is that the baby’s heart rate ? They came back again and did another abdominal ultrasound this time with the machine I can see inside the uterus and they said they saw the g sac and the yolk sac but didn’t see the baby or the heart beat yet. But when I was looking at it I thought I saw it flickering but they said I’m still early and it’s normal to not see anything this early. I go to my obgyn Wednesday I’ll be 7 weeks exactly. When the hospital took my blood to see my hcg it was at 100,000 last week it was at 7,300. I guess what I’m trying to say is shouldn’t I be able to see the baby and hear the heart beat with the hcg being that high ? I need help! This is my first time pregnant and I’m worrying about everything! The drs told me not to worry about anything cause everything looked normal I just need to reassurance!