Asthma and associated issues. Seriously!

I have felt like I have had a lung infection for a long time now. I keep trying to tell my doctor and ive been to the er over 3 times for these issues and no one seems to believe me. I believe I have a contageous infection in my lungs. I have been given cipro, bactrum, and other various antibiotics which work on the skin issues but not the lung issues. I am constantly stuffed up, feel like I cant get a deep breath, shortness of breath, headaches, stiff neck, confusion, feeling of fever (but my temp is always low) and everyone around me seems to get sick after spending time with me. I am not in a financial position to not work, but it is killing me mentally to know that I am possibly getting my friends family and coworkers really sick! I dont know what to do!! please tell me where to start, and what to say to my doctor or er staff to get them to take me seriously!