I had the same burning sensation you are
complaining, about 2 weeks after the surgery(which was in January) and had to put up with very cold air, when outside, e.g. 25 degrees. I'm not sure myself whether I have ENS, and I'm also looking into a clear, specific description and symptoms of it. You can check http://www.emptynosesyndrome.org for more info on ENS -- they also have a forum where people discuss symptoms.