why do i have itchy bumps an my arm stomach and thighs?

Could be a heat rash, or poison ivy/oak, or chicken pox. If you're running a fever it's one of the two at the end. If you're not and you've just been sweating and the bumps are in areas that rub together, then it's possibly heat rash. Don't scratch, put some calamine lotion and see your doctor.

Has it been hotter than normal where you are? If so, I would say most likely it is just heat bumps. I would say a heat rash. Just quessing. If doesn't go away in a day, Go to the Dr.

did you eat anything recently you might be allergic to? if so, i would take some benedryll and call a doctor. if you've been outside, then perhaps its mosquito bites or something...

Poison ivy?

hmm sounds like chicken pox to me

maybe it is one of these....chicken pox, poison ivy, poison oak, poison sumac, bug bites, rash, or an alergic reation

It could be anything. It's best to see a doctor.

chicken pox?