I have small red dots on my left arm like eight. they don't itch and there not bumps.?

Doctor can evaluate: Rashes are very difficult to describe in words, so an exam by a primary care doctor and/or a dermatologist is helpful, when the rash is present. Sometimes rashes occur from bug bites, fungus/yeast, reactions with chemicals, irritants, plants, allergens, etc... If one cannot go to the doctor, then taking a series of photos to show the doctor later is helpful.

Can't diagnose: This would require an in-person evaluation to accurately assess.