You may be able to feel the pacemaker under your skin as the pacemaker is typically placed just below the skin. This area will be sore after surgery, but as time passes the pacemaker should become less noticeable. During your recovery you may want to sleep on your back or side, as the area may be bruised or tender
The pain associated with an implanted pacemaker may be musculoskeletal or nerve related. Most likely related to the minor surgery required for insertion of the pacemaker. This type of pain related to the incision should heal within weeks. If you have persistent chest pain at the site of the pacemaker, it might be reasonable to see your doctor so that possible causes can be evaluated.