Thank you for writing.
Give the Flonase 7-10 days to see if you improve.
If you don't, then seek further advice since you have had these symptoms for several months. You may have a hormonal imbalance (including your thyroid) or you may have an inflammatory condition that is causing you this discomfort. Ask for an entire blood panel to be done to see if you have an autoimmune issue.
Please keep us posted and I hope you feel better soon.