I burnt chin with hot oily food. no blistering but very red and painful. two weeks in chin still redish purple. how long for discoloration to go away?

Skin type will tell: Darker skin leaves darker pigment behind. If you are fair skinned less likely fur pigment to stay. Avoid sun, use sunscreens and consider bleaching cream prescription by dermatology.

Redness: Redness after a burn can last for many months depending on your type of skin. Certain creams and bandages can help. See a derm for ideas.