Bug bite; infection?
Bumps on 3 separate parts of the body may be bug bites and/or may be small boils (skin infections; small abscesses).
A visit to one's primary care doctor is needed, as bumps are very hard to describe in words. Antibiotics may be needed, if there are signs of infection. Others causes of bumps are possible, but less likely. If the bumps are mysterious-looking, a dermatologist can examine them.