Hi, welcome to the forum, the probabilities of the rashes are Atopic dermatitis, Contact dermatitis, seborrheic dermatitis and drug reaction.
Other possibilities needed to be ruled out are viral exanthem, Mycoplasma pneumoniae - serological test and chest radiography is important to rule out and should be treated with appropriate antibiotic, Rocky Mountain spotted fever (it is tick borne disease and needs serological test for diagnosis), infectious mononucleosis, and scarlet fever; as a result of streptococcal tonsillopharyngitis, Kawasaki disease, and dengue. Hence, you need to undergo serological tests for few common causes.
You need to report if you have taken any suspected drug before this like sulfa drugs. Also any previous history of eczema, asthma, and allergic rhinitis should also be taken in to consideration.
Oral anti-histaminic and corticosteroid against prescription, which may help to alleviate these symptoms. I suggest you to consult a dermatologist. Take care and regards.
Could be the creams, soap, lotions you are using on your skin, I get rashes if I touch certain house plants, it sounds like something tyou are doing or even eating.What about Laundry detergent thats notorious for causing rashes .