Why Does My Period Keep Coming Back?

If your are pregnant and you keep getting period, this may be bodies way of letting you know that it was not meant to be.  I once tested positive for pregnancy, it was an empty sac growing inside, no baby, but for some reason, the egg had implanted itself and began to grow.  Best to have an ultrasound.  Even then, in early stages, they cannot tell about growth, but modern technology has come a long way since I had kids.   Have yourself checked out