Hey Sis,that is dysmennorea,a condition when your periods doesnt flow well...it may have different causes like Stress,not eating well,physical inactivity...so as a self treatment what u can do is:- to manage ur stress,Eat well,do simple exercise...totally try to modify ur life style and also u can use pain killers like ibuprofen(m for pain management but mind ur dose because it also have its own sideeffect...finally if your pain is not better with your home treatment you have to visit health center.Ayzon Sis