When a 7 year old experiences a head injury, several tests may be conducted to diagnose the injury..but again it depends on how severe the injury is. Physical examination may be adviced to assess symptoms and neurological function, imaging tests like CT scans or MRIs to identify bleeding or abnormalities in the brain, X-rays to check for skull fractures, and blood tests to evaluate various factors

You might have something we call a vasovagal syncope. Some of your blood flow may change for a short time when you sneeze this is what causes the feeling of faintness and may interfere with your ability to move your hands and legs for a while. Try sitting down or lying if you feel like sneezing. Also, make sure to drink enough water and have sufficient rest always. If it happens frequently or becomes more severe, see a doctor.

You are suffering from a tension headache. A typical characteristic of this problem is that you constantly feel like a tight band is wrapping around the head. A person may get this headache due to the brain's reaction to a stressful, tense environment, constant poor body mechanics, or eyestrain. One way to alleviate it is to relax, maintain good posture, and have screen breaks. Easy and gentle exercises for the neck can also be quite helpful. In addition to keeping your body hydrated and well-rested, you can treat yourself to a regular massage.

Inhaling gas, taking alcohol and some drugs can be dangerous especially when coupled with lack of sleep and food. Symptoms such as headache and shivering might mean that your body is stressed. Take a rest, eat well, and keep off harmful substances.

Seems that insomnia and the sensation that your brain is heavy might have appeared after you consumed two 400mg Vitamin E capsules. The reason is that Vitamin E overdose suppresses the nervous system and symptoms like insomnia which may be accompanied by feelings of confusion. Get enough hydration, eat well, and stay away from Vitamin E. 

The symptoms you mentioned may point to different causes like problems in the inner ear or variations in blood pressure. Since the last attack was a couple of months ago, it’s good that things have gotten better. Nonetheless, if they return or become worse than before, don’t hesitate to see your doctor immediately. Keep noting down how you feel and when it happens. Sharing this information with the doctor will assist in diagnosing what might be happening and devising an appropriate intervention plan.