I have also had this same experience. (symptoms below).
I think I have an allergy to
Flonase! The details of severe and less severe side effects of the drug are found here:
http://www.rxlist.com/flonase-side-effects-drug-center.htm
I think it's the Flonase, in my case adverse reactions are: mild swelling (throat), sore throat, white sores/dry spots in the throat, nausea and vomiting, sinus irritation and congestion, pain in the lymph node area.