Brief Answer:
Parotid or lymph node swelling. Add on anti-inflammatory.

Detailed Answer:
Hi.
Thanks for your query.
Seen the photo, noted the history.
As per the history and photo this can be one of the following:
If the ear lobule is also elevated this is most probably a swelling related to the parotid gland.
This can be due to lymph nodes enlargement.
Can be confirmed very well by high resolution Ultrasonography; FNAC that is fine needle aspiration cytology if this is due to lymph node enlargement helps in establishing the diagnosis. Contrast enhanced CT scan helps further along with the tests of blood and so on as would be advised by your Doctor.
Please get these done to get a proper diagnosis.
Amoxicillin is better taken three times a day since the swelling is painful and tender.Also take an anti-inflammatory with painkiller properties like Ibuprofen if it suits you.
Take liquid diet, stop chewing.
Hot fomentation.

I hope this answer helps you in proper diagnosis and plan for further management.
Take care.
Please give feedback once the tests are done.

With Regards.
Dr T Chandrakant.

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