hello there ,
According to your clinical history i suspect you have suffering from acute pharyngitis
It is inflammation of the throat mucous membrane
caused by bacterial or sometimes viral infections seen post flu infection .
It presents with symptoms of sore throat, pain and difficulty in swallowing ,fever , cold , headche as you have mentioned.
i would suggest you to start with antibiotic augmentin 625mg along with analgesics with antipyretics for 5 to 7 days.
maintain good oral hygiene
, use lukewarm saline water or antiseptic mouthwash like chlorhexidine
or betaine for regular oral rinsing.
i hope this helps ,