What Causes Sharp Pain In Chest While Taking Deep Breath?

3 weeks ago I had a mild cold with only one or two days of sore throat and no coughing. After that I started to notice my chest hurt if I took a deep breath in...as if I had just been running in cold air. I have had it now for 2 weeks. It doesn t appear to be getting worse but it is also not getting better. I still have no coughing nor do I feel it when I am breathing normally. Only if I take a deep breath in a get an aching in my chest.