What Are The Red Spots On My Scalp, Chest And Stomach?

Hi well I have,similar problems as all these people, but I guess mine started in my hair. When,i cut my,hair short I see them there red spots as big as a quarter. Also it seems like I have dandruff but the weird part is that I know its not dandruff. Then there is the spots developing on my chest and spreading down my stomach. Ive tried alot of remedies but cant get,rid of any of this, can someone tell me what it is that I have?