Brief Answer:
You should get yourself checked up by an ENT specialist properly...

Detailed Answer:
Hello and welcome to 'Ask A Doctor' service...
I've gone through your query in detail...

First and foremost, any unnecessary antibiotics should be avoided (the dosage that you mentioned here is insufficient as well)...You should get yourself checked up by an ENT specialist properly...based on the clinical findings, the further necessary investigations, as well as treatment, can be started by the ENT...

Till then, you can do the following:

-Do warm salt-water gurgling three times a day
-Check the body temperature for any fever
-For headache and pain, you can take Tab. PARACETAMOL 650mg after some food for the time being (can be taken up to three times a day)
-Avoid sour, spicy foods and have simple nutritious homemade foods for now

-For acidity and reflux, you should take a few precautions as well as taking PPI/antacid for a few days to observe how it stays. Medicines like Capsule PANTOPRAZOLE/DOMPERIDONE (40/30)mg once daily on an empty stomach (before breakfast) can be tried for about a week.
-Have some smaller but frequent quantity of meals instead of a large meal. Drink plenty of water throughout the day (only proper R.O or mineral water, no outside water strictly)...
-Avoid going to any over-crowded places, and use face-mask esp. during going outside...

Don't worry, but don't delay anymore and get yourself checked up by the ENT specialist for further evaluation and management...

Take Care
Kind Regards

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