Since laparoscopy and hysteroscopy and endometriosis removal in september,i have had lower pelvic pain for a few days after period.what could this be?

Residual endometrios: Endometriosis is, by definition, the presence of tissue that usually lines the uterus elsewhere in the body - usually within the abdomen. At the time of menses it too bleeds. Free blood within the abdomen causes pain that is sometimes confused with other infra-abdominal conditions. In your case I would suspect residual endometriosis in the Fallopian tube which is difficult to deal with.