I just started spotting dark brown blood a couple of days ago.  Went to the doc for my first prenatal appt and immediately got an u/s-everything looks good and I'm 7 wk 3 days and baby has strong heart beat.  I'm still spotting, and although I know everything looks ok with the baby (as of yesterday), I am still really worried that a miscarriage is in my future.  Anyone else experiencing this??