Brief Answer: No. It is Parosmia. Caused by Sinus infection. Detailed Answer: Hello, I have gone through your query and understand your concern. Nothing to concerned about. Now you are suffering from a type of smell disorder called Parosmia. As you have the recent history of sinus infection, this might be the cause for this sense of smell of ammonia. Sinus infection is a upper respiratory infection. This infection destroys the sensory nerves in the nose which sense the smell. This lead to inability of these nerves to encode and send the correct signal to the olfactory bulb, which serves as the processing center for smells. As the nerves are destroyed, you now perceive the smell of ammonia. Nausea could be due to stimulation by this false sense of smell of ammonia. You need the further testing for smell by presenting different odors of substances. At present there is no cure for this Parosmia. But it may diminish over time. Do not lose your hope and do not worry. Your sense of smell will return to normal after sometime. Hope this helps. Please write back for further queries. Wishing you good health.

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