Brief Answer:
follow the advice, observe how you stay afterward...

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

Well, as per your description, this could be due to an enlarged lymph-node below the chin region (although it's a bit too early for such swelling to appear)...

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.)...

Along with it, do regular warm salt water gargling three times a day for the next 2-3 days...No cold drinks/cold beverages (avoid curd/cold milk beverages for the time being)...

Additionally, apply some dry heat/heat-pad/warm compresses over the affected region three to four times a day and observe how it stays...

With all these, it should regress over a period of time, however, if you notice the swelling is getting enlarged, excessive redness or pus formation, there's any fever, difficulty in swallowing, etc. then you should not delay any longer and get yourself checked up by an Internal medicine/ENT specialist...Antibiotics therapy 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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