Post nasal drip, gagging, retching, anxiety

Hi, I am 26 and for the past 5 years I have suffered with regular periods of post nasal drip.  Basically I get the sensation of mucus which feels as though it is stuck between my nose and throat. No amount of blowing my nose or sniffing can move it.  At times this can become so severe that it causes me to gag however this still does not shift the mucus.  The condition is always worse in the mornings and it takes the best part of the day for it to pass and move to a point where I can swollow the mucus.

I have tried many different nasal sprays, antihistamines, sinus rinses and decongestants however nothing seems to work.  The ENT doctor even removed my tonsils and adenoids (adenoids) however this did not help.  I have also been told that I have a deviated septum.

Exercise and anything that causes my breathing rate to go up makes the condition much worse.  It has got to the point where I feel anxious in any social situation as I am afraid of gagging.  This anxiety also makes the condition much worse.  In order to keep the gagging under control I normally have to carry a bottle of water around with me and some sweets to suck which together both seem to help.

Basically it has got to the point now where I am desperate to find a solution as it is having a negative effect on my social and work life. Many doctors that I have seen appear to be clueless.  

As I said earlier it started quite badly about 5 years ago.  Since then it calmed down and I only suffered with minor symtoms (symptoms) for a few years but in the last month it has got much worse again.

Any advice or suggestions would be greatly appreciated !

Many thanks in advance.

Kyle