What Causes Blisters At The Back Of Tongue?

I have a sore to gut, it feels like burned it on food that was too hot. On the back of my tongue it looks like a have bumps similiar to blisters and my tongue seems like there is a coating or film on it. At the same time my scalp has scabs on it mainly in patches they seem to ooze a clear liquid then scab forms. My lips feel very chapped. I have had this before. Next symptom I get is oral dermatitis roscea on my face. It only appears around my mouth, chin nose and will not pass my nasal area it will go up my nose as well. My tongue always burns. I have had this on and off for 5 or 7 years. But haven t had it in 2 years. I m menopausal and have hot flashes with vomiting and nausea. What the hell is this? I have been to doctors. No one knows what this could be. I do have allergies and always a post nasal drip. Help.