If it's painful, you can take a pain reliever like Tylenol (as long as you don't have any other medical reasons not to take it) and you can place some hydrocortisone on the area of the rash.
You can wash your face, but use a very mild cleanser.
If it persists, you probably should get to your doctor to ensure there isn't any infection or other issues that they need to give you a prescription for.
Hope you are feeling better soon!