Women are told that severe pain during menstruation is ‘just in the head’ or ‘normal’. But you understand your body better, and maybe the severe body pain is an indication of something else. Endometriosis is a condition in which tissue similar to that which lines the inside of your uterine wall grows outside of your uterus. It causes excruciating pain, particularly during menstruation. One cannot diagnose yourself with endometriosis. Hence it is crucial to get checked and know the right facts about the condition.