Pain in back and right side of head for two weeks and sometimes a jolting sensation on my whole head. what could this be? how risky is a head ct scan?

Not risky: There is small, unmeasurable, risk from exposure to x-rays. However, the risk needs to balanced against the information needed to make a proper diagnosis. Do not avoid the CT scan just because of the small risk of radiation. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.

Not at all: The risk is if there is many CT scans. Just a single scan should produce no effects