Most probably you have inflammation in the upper part of throat. Commonly it is due to infection, often viral. This is the reason for your pain.
So take rest.
Avoid mental and physical stress
as much as possible.
Take plenty of warm water.
Do steam inhalation.
Take a pain killer if it hurts much.
But if pain increases (suspecting secondary invasion by bacteria) then you will need a course of antibiotic (Co-amoxyclav).
For this you can consult an ENT specialist
Wish you good health.