I have too many to count but this one stands out. Decided to dye my hair as the gray roots were popping through. I put on the chemical formula, waited 30 minutes, combed it out and thought, great looks good. My kit came with the conditioner to use after colouring. The next morning I got up and was showering and dumped the new conditioner onto my head. It dripped onto my face and my scalp and face started to burn. Oh, god, I had coloured my hair with the conditioner, then tried to condition my hair with the hair colour forumla.