Asthma? or Allergies?

Sorry to post twice within half an hour of joining this forum lol, but i'm really having a hard time discerning whether my symptoms are being caused by allergies, asthma, or something else? Basically what im mostly concerned with is my breathing, it feels like I NEED to yawn at least once every five minutes or so in order to catch a complete breath... I know that this is not normal. My first reaction was oh, I was diagnosed with asthma when I was 4 (im 20 now), so its probably that. But whenever the doctors listen to me breath, my lungs sound completely normal (no wheezing). I dont have any chest tightness at all, my blood oxygen levels are always normal, and a chest x ray came out normal. I have discovered that I have a severely deviated septum and a lot of inflammation in my nose, and post nasal drip, so could mouth breathing be causing these problems? Im not sure if this has anything to do with it but I had a pretty bad allergic reaction to eating shrimp a week ago, I had large hives all over my body and body wide itchiness... I also noticed my breathing gets worse in the winter. Could an indoor, or food allergy be causing this symptom? Im really at a loss right now...

It's called "air hunger" (technical term: "dyspnea") and may be a symptom of a wide variety of issues.

Try to get on something for the sinus symptoms and see if that helps. If not, If I were you, I'd be persistant in seeking an answer for the cause of the "air hunger."