Re: burning/stinging sensation in roof of mouth/throat..
There are many possible causes for stomatitis (inflammation of mouth). First, look at tongue and roof of mouth to see if there is redness, white patches, ulcers like canker sores, large cracks in tongue, and swollen lymph nodes under jaw, in neck.Did your Dr check your for anemia, Vit B12 and folate deficiency? I would start there, as well as a candida culture for fungal infection. Then consider, if those are all normal, a possible autoimmune disorder and get tested for those, especially if you are having any other symptoms suggestive of those. The first 4 can be treated easily. The last category will be more difficult, but the the first 4 are most likely. If you are on any medications, look them up, as stomatitis is a side effect of many meds!