I had a cold at the end of October. I took Dayquil and I got less congested, but I still will have fits of coughing, sneezing, or nasal congestion still that will come out of nowhere. I real concern is that I have been struggling to breathe, I go to take a deep breathe and it feels like my lungs are tight and they like constrict and I cannot ever get a deep enough breath. I have also been experiencing shortness of breath in general and my chest feels tight. It has left me feeling exhausted and just run down. What may be causing my symptoms.