Babylove, you can bleed during pregnancy, but the definition
of menstruation, menstrual periods
, the rag, AF, monthly visitor, the curse, the red tide, etc etc is the bleeding you have when you are not pregnant.
Yes, someone who is pregnant can have bleeding. It is not a period. It is reccurent, unexplained vaginal bleeding during pregnancy. It is not common.
mslkpage gave you advice about what to do. Take a test if you think this bout of bleeding was not your period.