Brief Answer:
further evaluation by ENT specialist needed...

Detailed Answer:
Hello there,
Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concerns...

Well, it seems like there's some form of mid-inner ear involvement/blockade of eustachian canal (a small tube-like structure communicating between the throat and inner ear) which is causing such symptoms (it's possible as it's inter-communicated and such preceding respiratory tract infection and secretions can migrate causing further swelling in the mid/inner ear)...

First of all, start taking steam inhalation three times daily, and do lukewarm salt water gargling twice daily...Please don't try to put anything inside the ear canal (no earbuds strictly...)

Avoid any form of cold-drinks, dairy products and sour foods as they can further aggravate this situation...take an antacid daily (eg. Pantoprazole/Omeprazole etc.)...

Please drink a lot of fluids. Have plenty of warm liquids (soups, broth, porridge etc.), they'll act as an immunity booster and fasten the recovery.

Along with it, you should take a decongestant, eg. Phenylephrine (eg. Sudafed PE three times daily for the next 2-3days), you may need a prescription from your doctor for this.

It's good that all other check-ups came ok. No need to be anxious, all these should provide some symptomatic relief. However, for definitive diagnosis, I'd recommend getting an ENT check-up for further evaluation. Based on the findings, the ENT may advise an X-ray of the Paranasal sinus and Chest X-ray, initiate antibiotics therapy as well for a few days...

Let me know if I can assist you further.

Take Care
Kind Regards

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