Loss?

I went in yesterday for a repeat hcg and first scan. According to the first day of my last period I should be 7 weeks. Well my hcg came to 7425 and sac showing a gestational age of 5w and some days. My first hcg was taken on 8/11 and it was 4819. I’m scared. Maybe I ovulated later or maybe I’m having my second consecutive miscarriage. He didn’t see a heartbeat yet but then again it could be really early.... I’m preparing for the worst again. Anyone have insight? Is that number low?