My husband was in a car accident one month ago. Did have a concussion but not a bad one. Several disc messed up in his neck and back, bruised lungs, partial collapse of lung and bruised chest wall. Thursday morning he woke up with a lump on the back of his head. The middle of the head. By Friday evening it was gone, now tonight he thinks he is feeling another lump. He has titanium plates in his forehead from and accident 20 years ago suffers from major headaches everyday. We will call his doctor Monday. How serious does this sound.