A week ago i had a very weird period no pms , light and lasted longer then usual. this week i have experienced heavy brown discharge. could i pregnant?

Check a test : If you think you might be pregnant check then check a home pregnancy test. They are cheap, reliable and available at any pharmacy. The brown is likely just left over blood sitting at the back of the vagina.

Yes: Pregnancy is always on the list of possibilities when a woman has abnormal uterine bleeding. You may also be having anovulatory cycles (cycle without producing an egg from the ovary). If a urine pregnancy test is negative, i would recommend evaluation by your gynecologist, and treatment will depend on the cause of the abnormal bleeding and your current short-term pregnancy goals.