At one week lumps that you feel may be related to the corset or the sutures or scar tissue from the incision. Give it time to settle down.
Is not unusual in the early stages after surgery to have a lump caused by postoperative swelling. The best thing to do is to contact your physician and get his or her opinion of this lump and if any intervention is appropriate at this time. But do not Panic everyone is swollen this soon after surgery and lumps are common.