The Cosmelan treatment I had 15 days ago has made me about 4 shades darker than before. Does this mean it has burned my skin?

Really hard to say without knowing your skin type, skin condition, background history, including any sensitivies - skin allergies, level of photo protection and baseline as well as current photographic documentation  etc.. If you are under the guidance of a dermatologist, please contact them- Cosmelan has specific protocols of which me may modify slightly. As guide my protocols are below, however this can be modified according to the PATIENT, all the best, Dr Davin S. LimStep 1: Mask applied in Dermatology office

·      Skin is cleansed and prepared. I use an acetone mix or gentle alcohol mix

·      In some cases I use Dermaplanning as a prep, in other cases microdermabrasion to prepare your skin

·      The Cosmelan1 mask will be applied. Highest concentration is worse areas

·      The mask must stay on between seven and twelve hours.

·      A home after-care kit with detailed instructions will be provided. 

Step 2: At Home Cosmelan routine

·      After the specified time, the Cosmelan mask is removed with a gentle cleanser. I prefer QV Wash or Cethaphil wash. Keep things simple

·      Peeling begins two to three days after the Cosmelan 1 mask application 

·      Cosmelan 2 cream should be applied two to three times a day for 14 days

·      After completion of the phase 1 of Cosmelan 2 cream this cream is now titrated to be applied once a day