Hcg levels rising, but still bleeding

[Djayy]

So this entire experience has been quite interesting for me. I found out I was pregnant in January. They took my HCG levels at what they thought was 5 weeks and they were 2200, 2500 and 2800 so they were not doubling at all. The doctor told me to just wait it out, not much we could do. I started bleeding last Saturday, just brown at first. On Sunday it turned bright red followed my cramps. I went to the ER and they found only a gestational sac, and said I was then only 5 weeks. Took my HCG and it was 4000. Told me to check my levels again in 2 days and they were 7000 so they are doubling. It has been 5 days now and I am still heavy bleeding with clots and cramping. I don't know what to think and I don't have another ultra sound until Wednesday (6 days away). Has anyone else ever experienced anything like this ? If so what was the outcome ? What is causing this bleeding if it's not a misscarriage and if it is, why are my levels doubling ? Please help..