Hello. Last year i felt a burning sensation on the corner of my lip. I didn t think of it as any major issue although it was burning for most of the day and that corner was dry. When I took a look in the mirror a dark mark had appeared. The mark is still there. Today the same thing happened but it was closer to my chin . My skin was burning and now i have three large dark areas. Honestly, I am terrified and irritated by by flawed skin. What do you think is happening?