It may just be old blood since there is no cramping, hopefully that's what it is and i'm baffled by the change in your weeks, some dates are mixed up somewhere or the baby is'nt growing as fast as it should. Anyway i want to wish you luck honey, keep us posted.
i wish you well and all the luck in the world for you to continue having a healthy pregnancy, but just how you have described is how mt m/c started at 9 weeks, my cervix was closed so i had a scan it revealed a haemorage on the lining of my uterus inside the preg sack but the baby was fit and well heart beating and very happy we got pictures and cried with relief,3 days of complete bed rest later i went to the loo and passed several clotts the size of oranges i knew instantly i had miscarried. it's very hard to accept a m/c after seeing your baby fit and well but these things happen for a reason, whilst i was being checked over before my scan the doctors thought i had caught a 3rd period so hopefully this will be whats happening to you, maybe your not as far on as you think and prehaps its a period. i wish you well and all the luck in the world.
Unfortunately its impossible to know for sure. Many women will have spotting and bleeding first trimester and all is just fine. Your next HCG count (thats the hormone blood test) will tell them something, and you probably need to have another ultrasound in a week to check for growth. I know this is a scary time, and the waiting is the worse. There just isn't any answer right now except to wait and try to stay positive. Did they see a heartbeat? Also, are you positive on your dates? Please let us know how you are doing. Take care, and I wish you all the best.