I have a few red spots on my chest, and now they are turning dark brown and the spots are speeding all over my chest. I am not itching or irritated.?

Many possibilities. If it's symmetrical it likely has an internal cause, such as eczema or a virus. If not symmetrical it more likely has an external cause, such as an allergy to something you have contacted. Try an otc Hydrocortisone cream, and if that does not help see your doctor or a dermatologist for a precise diagnosis and more specific treatment.