Been having brown discharge over a week and sometimes dark red blood. my period is over 3 weeks late but i tested negative to pregnancy.

Missed period: You may have a genital tract infection and also bringing out old menstrual blood. See your doctor.

Common : Irregular periods are one of the most common problems obgyns treat. If this is one time problem it usually resolves on its own. If this is a recurring problem you should be evaluated. Infections, polyps, fibroids and hormonal changes can cause spotting. There are many options available to help regulate the menstrual cycle. Schedule a visit.