I have been suffering come-and-go rectal/anal pain, back pain and pelvic pain during period for the past two years. my period ends a week ago but i have been suffering from the same symptoms for the past two days even though im not on my period. so i wen

Endometriosis?: See you Family Doc and get checked out for endometriosis. Your symptoms sound severe, especially to have started in your teens! It is especially telling if you have deep-penetration sex pain. Plan on having a pelvic exam and an ultrasound for a complete evaluation. If it's not endometriosis, then those investigations will take you closer to a diagnosis and then a treatment.