How Can Difficulty In Swallowing And Post Nasal Discharge Be Treated?

I am not sure what is going on . I have been to two doctors about this problem and they either do not know what the problem is or they do not want to help ? This all started with a case of food poisoning from a spoiled piece of roast beef. After violently throwing up for 24 hours my throat has been dry and my mouth and throat have a thick foul tasting coating and I cant get it to go away. I have constant sinus drainage going down the back of my throat. have taken anti biotics but they dont seem to work. My sense of taste is gone, virtually everything is hard to swallow because of the dry issue. One Dr. an ENT guy told me that my esophagus was really raw and irritated and the greenish yellow drainage from my sinus is my body trying to protect my esophagus by flooding my throat with this nasty drainage. I dont know whether that is true or not. Sound a little fishy to me .