Hello
Let me explain you a thing that according to your history of illness ( in query ) you were never a patient of flu ( amoxycyclin and doxycycline didn't work ).
Breathlessness , 
cough ( dry ) 
tiredness , lungs not working properly ( according to you) as these symptoms may be due to .
Asthmatic allergic 
bronchitis , this is a common feature of 
allergy. Mite , dust , pollen ,mold , sudden fall & rise of temperature , humidity , fine powder, hay , fodder ( dry ) , smoke all  are predisposing factor of these symptoms .All these symptoms present due to 
bronchoconstriction and whistling sound is a common feature during breathing. 
When such type of patients visit  in my clinic I usually prescribe them monteleukast+ bambuterol ( combination ) tablet twice in day till complete relief. 
Hot coffee also helps.
Since this is a prescription medicine so please consult a physician and get his opinion.
Good luck.