Were kind of in the same boat. Im almost twelve weeks as well and started bleeding yesterday morning. Went to my regular OB and he sent me straight to our OB hospital here in our state. They did an ultrasound and an internal, saw my baby to and it looks great. Moving all around good heartbeat but im still scared out of my mind something is going to happen to my baby. And I feel exactly the same, if I lose my baby I dont know what ill do. I to had a miscarriage in august, I was 6 weeks 4 days. Drs are telling me the same thing now, its a threat for miscarriage but as long as the bleeding stays light everything should be ok. Not very reassuring in my book. This is my 5th pregnancy and nothing like this has ever happened to me before and im freaking terrified as well. Im sorry your going through this and im hoping that everything goes well for you.
I had the samething i had a threatened miscarriage til i was 15wks usually it goes away on it's own as the baby grows it shrinks just take it easy n no sex, I'm now going to be 34wks n everything is going great with my pregnancy!! Good luck to you