Brief Answer:
Infection/ inflammation of paranasal sinuses (Sinusitis)

Detailed Answer:
Hello dear,

Thanks for your query.

Regarding the symptoms as mentioned in your post, kindly let us know about the following:
1. Any recent episode of illness or surgery in the nose?
2. Any history of expose to chemical fumes or smoke?
3. Past history of systemic illness like Hypertension, Diabetes, Thyroid disorders, etc.?
4. History of recent or prolonged intake of any medication?
5. Any other associated symptoms?
6. Any recent history of Stress, improper nutrition & lack of sleep?
7. Habit of smoking or alcohol consumption?

If your answers to the above mentioned questions is "NO", then the symptoms can be attributed to infection/ inflammation of paranasal sinuses (Sinusitis).
Due to this, the sensation of smell (Olfaction) is affected and you are experiencing the acidic odour.
This inflammation also blocks the sinus drainage and cause increased mucus production. The mucus drains from the nose and sinuses down the back of the throat causing a postnasal drip.

Clinical examination is important for diagnosis, so I will advise you to consult your Doctor for a proper clinical examination.
Investigations like complete blood count & X-ray of paranasal sinus will be helpful in clinching the diagnosis.

Though symptomatic relief can be obtained with Fluticasone nasal spray and saline wash, the underlying cause needs to be treated.
A course of antibiotics will be needed to tackle the causative organism. Maintain adequate hydration & a healthy balance diet. Also make sure that you are well protected from cold, dust & other allergens.

Wish you good health & a speedy recovery.
Take care.

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