Can a patient have real shortness of breath if they are still able to breathe using only their nose? i cannot tell the cause of my chest discomfort.

Yes.....: You can be short of breath while breathing through your nose. The combination of chest discomfort and shortness of breath can be due to many things, including serious conditions that can be life-threatening, like heart disease, blood clots, bronchospasm, etc. In order to be certain there is nothing serious going on, you need to see a doctor ASAP! Go to the ER, especially if feeling worse