Heartbeat

Went in to hear the heartbeat today and everything was great. The HR was 156 and sounded good. And then the doctor told me that my blood type was A-negative and I am also Rh-negative which means that my antibodies are at risk for fighting off baby's blood cells if baby is Rh+ (which it probably is). So at 28 weeks I will have to get a RhoGAM shot to hopefully prevent any defects, anemia, or anything else. After reading more about it I am kind of stressed out about it....