I have red dots all over my stomach, sides , back and arms. i am under the care of a rumotologist because my ana tested positive. so i might have an autoimmune disease. i have past history of leg rashes. however i did use a new soap?

This could be an autoimmune vasculitis which causes leakage of red blood cells out of tiny blood vessels in the skin. I wouldn't expect itching as you'd often experience with allergic reactions. Have your rheumatologist examine and advise you. Appropriate testing such as a cbc& diff with a platelet count,pro time,ptt,lupus anticoagulant for example or you may be referred to a dermatologist.