I have a rash on my face, dry, cracking scaly skin, burning, tiny bumps all over face. came overnight. 3 days ago. painful to move face or open mouth?

Localized rashes: A rash focused on one site of the skin surface is usually a response to a local contact with a triggering agent. Think of a skin soap, lotion,perfume, makeup remover, etc. that you may have applied in the area. Such a response would come up no more than 18-24 hours later. It should fade if you avoid the product & keep the skin clean. Otherwise see your doc.