What Causes Red Bumps, Burning Skin, And Stabbing Sensations Triggered By Heat Or Warmth, Worsening Over A Year And Spreading To My Legs?

My skin is heating up, it is devaloping red spots and bumps. Whenever ever i get hot or warm in any sourt of way, it feels like needles stabbing me over and over again. It comes in waves, i contacted 6 doctors no one had a clue to solve it. I need help this is an emergency and it is starting to spread to my legs.(i can not to excercise or anything because of this case, its also been a year and its getting much worse)