What Do Red Bumps Appearing On Skin Indicate?

random red bumps appearing on my skin- not rash like, but individual bumps, started in middle of night and gotten worse through day. they are not bites of anything (nothing in bed, and have kept appearing through out the morning)... mainly on legs, a few on tummy, back and neck. none on head, hand or arms. never had before, not poison ivy, reminds me most of when i had chicken pox. could it be allergy to something? have not changed detergents or eaten anything unusual.