My age is 24 years. Iam unmarried. Iam facing problem of periods from last 2 to 3 weeks.There is continous little amount of bleeding from last 2 to 3 weeks. And the color of the bleeding is little brown sometimes it is also black in color. I did not face this before..Iam so tensed about this..can any one suggest me what may be the reason..is it dangerous?? Please say me whats the reason behind this??