1. Apple cider vinegar does not smell great. Once the toner dries on your face, the smell almost completely dissipates, in my opinion. If the smell does bother you too much, let the toner dry on your face and then rinse if from your face quick with a splash or two of water, before applying your moisturizer.
2. This may sting on sensitive skin, any wound, and scratched pimples but if it stings more than 1-2 minutes, immediately remove the mask from the face and clean it with water and apply aloe vera or witch hazel.
Always do a patch test before applying it.