To be quite fair endometriosis can be difficult to treat if it winds up on another organ. Hopefully though your doctor removed everything. However under most bornally circumstances your surgeon should have removed everything (if he didn't he would tell you). There is no definite way to tell but if you are in pain and depending on when you had the surgery I would follow up with OB/GYN. Aside from that there is no real definite way of knowing.
