I had a tumor removed from my back a week ago
Based on your description and photo, you appear to be having normal healing. The "knot" is most likely related to the sutures closing the wound and/or swelling around the operative site. You would need to have your surgeon assess you to understand this fully.If your symptoms progress, and/or you develop fever, chills, sweats, drainage, etc., you would need to be seen on an urgent basis. Otherwise you seem to be recovering appropriately.You need to be seen in person to be sure.I hope that this helps and good luck,Dr. Alan EnglerMember of #RealSelf500