I need success stories. Freaking out!!!!

I had my first ob appointment today. Based around my ovulation time I should be near the end of the 5 week mark. I had an ultrasound and blood work done early in my 4th week. My hcg was 189 and the ultrasound revealed nothing. I went for a repeat hcg 3 days later and it was 608 so I patiently waited for my appointment today. Well all they managed to find was a tiny sac but nothing in it. So again I was sent for blood work. It’s been 7 days since my 608 reading and my levels are only 1500. Now I have to repeat these blood tests again Wednesday. They can’t rule out ectopic and another concern is the pregnancy isnt viable. I’m so confused and just am wondering if anyone else has experienced something similar and gone on to have a healthy pregnancy. Thanks for all your help!