If you've ever dyed your hair at home, you're probably well-acquainted with the section of the instructions that urges you to conduct a patch test before really going for it. This, of course, is to ensure that you don't have some sort of allergy to the dye.
I'm pretty sure most people ignore this suggestion, and 19-year-old Estelle is no exception -- but the decision nearly killed her. Her head literally swelled up "like a light bulb." Check it out below.