Is it acne or is it a rash?

Im 16 and I seemed to of gotten this itchy rash, on my chest Back and arms my scalp is itchy and flakey and I never had dandruff before. It is not inflamed, just small red pimples and there not pustulents like acne should be. I have pictures and i am worried they are chicken pox , altough i had them before I heard you could get them again. Im worried because I only got it 3 days ago. Im gratefull for any help Alanna x      

[loiloi]

Hi. It would be very unusual to get chickenpox twice. Chickenpox lesions are quite distinctive and look like "a dew drop on a rose petal" The rash starts on the trunk then spreads to the face and extremities.
Acne does not tend to icth and occurs on oil-rich areas of skin such as the face, chest and back.
You may have a condition called Seborrheic dermatitis, but repost this photo in the Dermatology forum, as i am only an expert on acne.
This could be an allergic rash, if you develop any other symptoms such as difficulty breathing, closing of the airways or swelling of the tongue or fingers seek medical advice immediately.
Eloise.