Spotting But Baby Is Fine

Last week at 7 w 5d I started spotting, brown then pink when I wiped.  Had an ultrasound and baby was fine w/ a 127 heartbeat. A week later at almost 8 weeks I noticed red blood when I wiped. Had another ultrasound & baby is fine, with a heart rate of 167 this week.  I was so relieved.  I wept for joy!! The Dr. Thinks there is a small dip in my uterus (Arcurate uterus) that is causing this spotting. She said there are no signs of an impeding miscarriage & all should be fine.  I am still spotting, brown & pink now, & even though the Dr said all is ok, I am so scared all the time.  Anyone have any spotting success stories or an abnormal uterus?