What Causes Cough Upon Breathing Deeply?

Hello. I have never used this before. I am trying to figure out if I need to be seen. I started feeling a little run down yesterday afternoon, then developed a shallow cough when I take a deep breath. My ears and throat are burning, and my chest feels like there is a weight on it. I have had my lungs checked and they are clear. I feel overall achy and have been freezing all day (but no fever). I thought maybe it was the flu, but I have no fever, not even low grade.