Welcome to the forum. You should have an oral swab test done. Investigations help to detect the cause of your illness and aid correct diagnosis to get you treated well without losing much time. Your symptoms have been persisting for more than 10-12 weeks, you should get few blood tests and radiography
done to rule out any pulmonary disease. Sputum tests for acid fast bacillus (AFB ) should be done.
You have not given history of any past illness. If you have sinus
problems in the past you should get an X-ray PNS done. Antihistamines, Mucolytics and expectorants can give you symptomatic relief.
To get cured well co-operate with the doctors and get diagnosed. After you are diagnosed take antibiotics in proper dosage. Take care of your diet and keep yourself well hydrated. Have a nice day.