Recently I have been improving on my vocal ranges. I was able to sing higher octaves while sounding good. However, a few weeks ago, one of my tonsils was red and a little bit swollen making it difficult to swallow, cough, or sing. I went to the doctor's and she said that it was a minor infection caused by some nasal activity (I don't quite remember). My tonsils isn't swollen anymore nor does it hurt. However, now when I sing it has become more difficult to reach those high notes when I sing. It comes out very breathy and less clear.
Melissa Kim M.S., CCC-SLP replies...
There could be any number of reasons for your vocal difficulties. I would suggest that you seek out an Ear, Nose, and Throat physician for an evaluation and treatment recommendations.