Thank you for your query at DoctorSpring.com
Your child seems to be having one of the two-
Serous otitis media with effusion secondary to an upper respiratory tract infection or primary suppurative otitis media
The first one is more benign, but both essentially mean that your child has an infection of the ear.
To provide immediate pain relief, you can administer paracetamol 15 mg/kg per dose three times a day. If the pain is very severe, you can add ibuprofen 10 mg/kg per dose thrice daily to it.
You need to give your child plenty of fluids and take him to a paediatrician to get his ear examined urgently. If there is any evidence of ASOM, the second diagnosis that I had aforementioned, then the child needs to be given oral antibiotics.
Wishing your child a speedy recovery.
Dr. Saptharishi L G