you have a long standing cough
which needs a compleate investigations including Hb%, Tlc
,Dlc, Esr, Mx. test, blood suger,x ray
chest, evaluation test, stools test for worms,skin exam. for exema or infection ,sputum culture
&many as per need. Please consult a chest &allergy
specialist to get a specific diagnosis &treatment.
In modern medicine any thing &every thing has treatment so please don't worry.&don't neglect.
You also need few lifestyle changes.
-Eat healthy&low calory food ,avoid the food that instgates cough.
-do mild exercises daily inpollution free atm.(walking)
-Do respiratory exercises (Pranayama)daily
-avoid exposure to cold
-try to be more hyginic -viz.- holding hankerchief on mouth while speaking,coughing.aviod spitting in public place. you should spit in a basin with open tap-running water. this will avoid spread of bacterias & people will interact with you safely.
Sorry, if I am v. straight forward,but it's for your own benifit.
wish you all the best.Thank you.