Hello. Thank you for your question. I am sorry your son is experiencing these symptoms. Usually periodic dizziness or light headedness, with or without headache, is attributed to mild dehydration. In your sons case, however, there is occasional visual disturbance and definite headache. Though this could be a sign of migraine headache, or something football related, it is difficult to diagnose without a full evaluation. I recommend a consult with a pediatric neurologist to help make the diagnosis. in the meantime, your son should keep a headache diary, detailing day/time of headache, how long they last, what activity he may have been engaged in (ie: sports, video games, eating, etc...) what made them go away (ie: ibuprofin, rest, etc...). This will be helpful in pinpointing the cause.