What Causes Severe Headaches?

My husband is not at all inclined to get headaches, but has been getting really bad ones off and on for the last couple of weeks. Today he is complaining of a severe one and it has me concerned since this is so abnormal for him. He has had an adjustment at the chiropractor and a 15 minute spot massage on his neck and shoulders this morning hoping this would help. Then he took some tylenol (2 500mg tablets). He is still in lots of pain and says that everything (light and sound) is bothering him. To me it sounds like a migraine, but wondering if he should be seen by a doctor to be sure?