For 5 days now I have been experiencing shortness of breath, a very subtle heaviness in my chest, blocked nose, the feeling that I am not getting enough air and a regular cold. My chest is in no pain, although sometimes I get very very mild, subtle hints of a dull achy pain. I am not coughing, or coughing up blood, I do not have a temperature or anything like that. What on earth is wrong with my lungs?