I called the nurse midwife line Thursday afternoon to find out the blood test results. The midwife I talked to said that my hCG levels were well within the "normal" range for how far along I am, but the levels didn't double as they would expect them to. She said she wasn't worried about it.
I asked if she could tell me what the heart rate was at the ultrasound, since Adam and I couldn't agree on what the she said. She said it was 124 bpm (I was right!). :) Then she asked if we had met with an OB or midwife after the ultrasound. I said no. So she pulled up the results of that. She said there was a medium sized hemorrhage behind the placenta (about 2x2 cm). She called it subchorionic hematoma (SCH).
I found an article online that said that 1-3% of women that get SCH end up miscarrying, but most of those cases are where the women has a large hemorrhage. I'm hoping that a medium-sized one isn't anything to worry about (the midwife I talked to said she wasn't all that concerned), but I'm still a little worried.