I have a really bad cough?

I've had a cough for about a month. The doctor said it was bronchitis and I've been taking medication for about a week and haven't really seen improvement. My main worry is that my throat gets full of phlegm and I basically choke. I usually throw up and make painful wheezing breaths in order to breathe again. It only lasts a few minutes, but sometimes it feels like it's not going to stop. My chest hurts like hell afterwards. Any ideas what's wrong? ^_^