Pregnant but still having periods
It is not possible to have your period during pregnancy. When you have your period the lining of your uterus is sloughing off, that lining was ready for a fertilized egg to implant and it sloughs off when it is not needed. During pregnancy that lining is used by the fertilized egg.
There are many causes of bleeding during pregnancy. Some of the causes of bleeding can even come every few weeks and mimic a period. Your doctor will need to evaluate you to determine the cause of the bleeding. Some bleeding is dangerous and other bleeding is minor with no long term consequences. Only your doctor can determine if you or your baby is in danger.
Any bleeding during pregnancy should be reported to your doctor right away.