i think you are right i have the same prob
are the bumps colored? hard, soft? itchy, sore?
sometimes you can get milia in those areas. depending on the size. milia are similar to pimples in that they are plugged sebaceous glands, but they do not come to a head and should not hurt or itch. the vary from flesh colored to white or light pink.
a dermatologist can extract them(minimal discomfort, does NOT hurt) and give you a good body wash to use to prevent it from happening anymore. if that is what you have going on.