Mottled Skin Mottled Skin, Rash Or Just A Result Of The Cold. Whats Wrong With My Arms?

Mottled Skin, rash or just a result of the cold. whats wrong with my arms? - mottled skin

Approximately 27 hours, I found my arm was very uneven gets blotchy skin occasionally, and then his arm, and today I have not changed abit like a rash, I think that my arms were very red and feels like I like the sun was been burned. Ive at my school nurse told me, here are some Piroton and see where it goes and then an appointment with the doctor, but I would not consult a doctor if I could find out what the Internet at first.
Who knows what can be?