Please help. Almost 6 weeks along. Started to bleed heavily last night with large blood clots. Tests…

Please help. Almost 6 weeks along. Started to bleed heavily last night with large blood clots. Tests show that my hormone levels are still going up. Doctor did an ultra sound and can see the embryonic sac in my uterus. She said she'll do another ultrasound in a week and recheck my levels then. But she said not to get my hopes up. I'm still bleeding a lot and i have cramping. I'm so scared. Has anyone gone thru something like this?