Pelvic Pain-What Could This Mean?!?

It's sounds to me like you might have pelvic inflammatory disease. If you are having unprotected I would go to the nearest women's clinic and have them give you a pelvic exam. PID would cause pelvic pain, explain your abnormal period color, headache, and exhaustion. PID is an STI and can lead to infertility. Please go to the doctor and get yourself checked out. In very rare cases PID can be caused by a bacterial infection. If you do have PID your partner needs to be treated as well.