Am I losing my baby?

Sh
We found out I was pregnant on 1st February. My last period day was December 23 but ovulated around  14th January. On February 13th the doctor said I was 5weeks and a day. Today, March 1 I should have been 7 weeks and 2 days but the ultrasound said only 6 weeks and 4 days and they didn't find a heartbeat. To top it, I started spotting yesterday- only when I wipe though. Very mild cramps. Is this pregnancy not viable? Anyone else faced this but took it to term? My heart is sinking and my eyes wet. 
UPDATE (March 2): the bleeding started later yesterday... so this is it then. Will be going to the hospital for a D&C. Thank you for all your prayers! I'm so grateful! 🙏🏼❤
UPDATE (March 2): Mother Nature loves her babies. She protected me and my unborn. I didn't need a D&C. The ultrasound showed the uterus has flushed itself. I didn't feel the prolonged severe pain that people refer to while natural abortion- just shooting pain for 10 minutes- nothing tylenol couldn't handle. I peed a few hours later with a gush of blood. They believe that was it. The best possible uterus cleansing naturally. Thank you everyone for your support. My prayers for you ladies bearing the loss. I pray it is at least not physically as painful, emotionally we just have to be strong! 🙏🏼❤
To answer my question: yes I lost this one. But my rainbow baby is just a few months away. Baby dust to all of you! 😘🙏🏼❤✨✨