After eating cashews, my tongue became very itchy, I had little red spots on my tongue an I felt a burning feeling. Could this be an allergic reaction?

Cashew. The cashew family is called anacardiaceae. Poison ivy, poison oak, poison sumac are all members of this family. Cells within the two layers of the cashew nut's hull secrete an allergenic resin. Cashew nut shell oil has 12 allergens and cross react with poison ivy, and mango skin and ginko biloba. So the answer is yes.