In spite of using inhaler often, I have heavy congestion. Why?

Hello doctor,

I have been to doctor three times in the last two months and was prescribed many medications. But, I am simply not getting any better. Initially, I went in for respiratory issues. I had a terrible hacking cough and was literally using my Ventolin inhaler more than I should. As I am asthmatic, I was placed on a nebulizer and given several other medications including Prednisone to take. After completing the medication the symptoms returned. I went back to the doctor who changed the antibiotic. It cleared up temporarily and again once the medication was completed, symptoms returned. Today, I am literally just feeling awful because I do not want to go back to a doctor as nothing seems to be getting better. I feel nauseous, I have headaches. I am using my inhaler frequently and there is still a very heavy congestion on my chest. I wake up in the middle of the night hacking. I cough until I cannot breathe. I overall feel dizzy, lightheaded and I have no energy. Please help.