All these symptoms indicate that your might be having Pharyngitis
Presence of high fever
& headache indicate infective etiology.
1. Gargle with warm salt water to relieve throat pain.
2. Analgesics like paracetamol
to relieve fever & headache.
3. Antibiotics depending upon culture & sensitivity reports to remove the causative organism.
4. Antihistamine preparations can also be used to provide symptomatic relief.
If symptoms still persist...it will be better to consult a Pediatrician
for further management.
Meanwhile...he should avoid taking cold
food & drinks, maintain adequate hydration & take soft, non-spicy foods.
Wish him good health & a speedy recovery.
Thanks & take care.