Hello, Delayed periods are indicative of pregnancy, if you are sexually active and had unprotected sexual intercourse and was not taking regular contraceptive pills or emergency CP. Get a pregnancy test done with the first morning mid stream urine or a blood test for pregnancy. If positive, get clinically examined by a gynecologist, you will be managed accordingly. If test shows negative report, then your gynecologist may order few blood tests and ultrasonography done to detect ectopic pregnancy or any other pathology that could be causing you symptoms. You will be according treated. Anemia, poor general health, obesity or low weight, PID, PCOS, thyroid problems commonly affect menstruation. Get treated at the earliest. Get pregnancy test done before taking Deviry. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician