Had the ultrasound this morning, and there was a baby and a heartbeat!
I am cautiously optimistic, and exhausted.
It was a subchorionic hemmorhage, as SumnerRain described. But these things can vary a lot in size/severity. Although most times they are relatively harmless, when severe enough they can cause m/c. Mine was large. Which I already knew, because I was gushing blood yesterday--like 3 huge postpartum pads soaked through with bright red blood. Physician said that it was good that the baby had survived the hemmoraging. So hopefully that will be it; over time the tear will heal. But, this could continue the entire pregnancy. Or worse, the pg itself could still end.
But, for now, we have a heartbeat. I was surprised, and thrilled.