Thank you all... Well it is kind of a relief to hear your feedback. I will speak to him and try to sort things out, can get my mom to chat with his parents too. Once again thank you all....
If your cousin is on the computer too much, that can cause what is called migraines (headaches with feelings of sickness and seeing white marks).
He may need to have glasses.
He may also be anaemic, or may have a mild tummy bug or he may even have a throat or ear infection.
The bump he had on his head when he was 2/3 will have nothing to do with how he feels now. My son had concussion when he was 9 and he has no problems now.
His mum should definitely take him to the doctors to check him out.
If your cousin's parents won't take him to the doctor, I recommend telling him to go to the school nurse to tell her about these symptoms. I think she'll probably tell his parents that he needs to be seen by a doctor. Considering that there are vision problems involved, he could also tell a teacher if he's not comfortable with going to the nurse. Could your parents intercede with his and say they're concerned? There are a lot of things those symptoms could mean, but he should Definitely be seen by a doctor in case it's something serious. It's not from bumping his head a decade ago or playing video games.
Even if it's nothing serious, it can't be fun for your cousin to have those symptoms, so it would be nice to find out if there's a treatment. I hope his parents will get him to a doctor.
Your cousin may be clenching his teeth at night. Or he might have sinusitis causing sinus pressure. It could be related to barometric pressure, food allergies, dust or mold allergies, or hay fever.
Your cousin could try avoiding dairy and drinking more water. He could try a saline nasal flush. He could be seen by the doctor about allergies. Does your cousin have dark circles under his eyes? Does he sneeze or wipe his nose or rub his eyes or get hives or itchy throat? Or does he have pain in his face over his cheeks, behind his nose, or around his eyes and forehead?
If he is clenching or grinding his teeth at night, he needs to practice relaxing his jaw muscles, stretching and massaging the muscles. He may need a bite guard.
I doubt it has anything to do with falling on his head so long ago.