Am so scared

I feel like am going to unhinge seriously last month I had an early miscarriage. The doctor did an ultra sound found nothing. Although I was still testing positive we did a scan this week turns out am pregnant again.. Although the doc says he doesn't know if it's viable because he sees a sac but no egg fetus. I told him the only time I could conceive was sep 2nd! Two weeks ago so he's giving me the benefit of the doubt and will ultra sound again in two weeks to see if there's a change!! Plz pray for me because I can't have 2 miscarriages in 2 months. I feel emotionally drained