I have a very bad cough, producing mucus that s mostly clear but can also be yellowish in color. Constant congestion in sinuses, head pressure, and body aches from coughing so hard. Having a very difficult time falling asleep, because every time I lay down, I start coughing. I actually feel better the longer I sit straight up or stand. This has been going on for about 1 1/2 weeks now. Can you tell me what I have?