Ah, sneaky sneaky! lol did you spray it with something after to make the powder stay on?
actually, when u apply the powder BEFORE baking, it makes a permanent bond (however, still need to avoid swimming with the mask on, on wearing during sports---not that one would do either wearing the mask, but still).
when u apply powders or acrylic paints BEFORE baking, makes a more permanent bond, and needs no sealing. however, when applied after curing, must be sealed with a product