The way to self development is not an easy going, peaceful journey there is a price to be paid. One of these penalties, I believe, is headaches. For the sake of imagination and fun, I am referring to the Hulk character. You may have noticed that before and during the transformation the person encounters a painful headache, but after the transformation his new mode is anger but there are no more headaches. In our present times, people seek to escape headaches through painkillers. Many times these headaches could just be malnutrition or oxygen shortage in the brain blood vessels. There are many biological/physiological reasons for a headache, but there are also spiritual/psychological reasons and I believe that occupying the mind with a specific problem for a long period of time may inflict permanent personality changes whose initial symptom will be a headache.