I am going through something!!!

Hcg started at...

1st 10

2nd 24

3rd 55

4th 124

5th 255

6th 568

7th 667

8th 673

I had an ultrasound and they saw a sac but couldn’t see any yolk sac or baby...they measured the sac at 5.6mm but wouldn’t date my pregnancy...idk what’s going on and could use some insight....there is no bleeding and no cramps. This would be the 3rd miscarriage in a year. Anyone have anything like this and they have a healthy baby. Have another ultrasound Wednesday. First ultrasound was Tuesday last week. PLEASE HELP EASE MY MIND....