Why is my tongue SO sensative to sour stuff?

About a week or two ago I ate a whole bag of sour skittles. All was fine until a few days later, my whole tongue turned white and I had to go to the doctor's & get medicine. My tongue hurt really bad, like it was itchy and there were all these cuts on my tongue. Now it's happening again, all I did was eat some starburst yesterday! They are hardly sour, just citris-y, I learned my lesson to stay away from sour candy, but I didn't think the starburst would do any harm! Why is my tongue reacting like this, it hasn't before! & What can I do about it? Thanksx.