i am a 40 year old female smoker. I had an upper respiratory infection and was given a 3 day z-pack and benzonatate for the cough. that was on Jun 20 it is now the 29th of jun and I am still coughing and when I lie down I hear rattling I guess from my chest I cough and it goes away, nothing comes up but in the morning I have a lot of phlegm. My back started hurting the first day or so I got sick my lower back that is. My back has seemed to have gotten worse I have been trying to stretch it out but that makes it worse I just need comfort and be able to sleep during the night. please help if you can