Brief Answer:
could be due to an impending Flu... rest yourself, observe how you stay afterward...

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

First and foremost, stay in a warm and dry place as long as possible (indoor), and drink plenty of warm liquids (soups, broths, porridge, bournvita, etc.)...avoid going to any overcrowded places for the time being...preferably, take rest for a few days until fully recovered...

Along with it, do regular warm salt water gargling three times a day for the next 2-3 days...along with it, also do Betadine gargling twice daily in an alternate fashion for the next 2-3 days...

No cold drinks/cold beverages (avoid curd/cold milk beverages for the time being)...drink plenty of lukewarm water throughout the day to keep yourself well hydrated...

For headache, body ache; Crocin can be taken up to three times daily after some food...I wouldn't encourage taking it for temperatures below 37.8°C though...

With all these, it should regress over a period of time... However, if you notice any persistence of fever, worsening of present symptoms then you should not delay any longer and get yourself checked up by an Internal medicine/ENT specialist...Antibiotics therapy may need to be initiated in that case after evaluation...

Not to worry...just follow all these and observe how you stay in the first place...

Let me know if I can assist you further...
Wish you good health...

Take Care
Kind Regards

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