I got sick almost 4 week ago now, and the only thing that seems to have stayed is my cough and always feels like mucus stuck in my upper chest/lower throat, It tends to come out clear with some brown in it, and a few times a dark mustard color, I've called my GP and they never call me back been to a express care, they say its not pneumonia and send me on my way, I just want to know what it is, sometimes it can get hard to breath.