Hi.. The Back Of My Throat Hurts & Burns When

Hi.. the back of my throat hurts & burns when I swallow. A couple of hours after I go to sleep at night I am awakened by coughing & coughing up flem. It feels like there is a lump in my throat & my tongue hurts & burns too. I have had two doctors look at my throat & check my glands & everything looks normal to them.I am a non smoker & I have not had a cold.