It will be best to see the picture of the spots (you can upload it) or know about more symptoms of the spots.
Symptoms: Are they itchy? Are the spots red? What factors trigger the spots?
It may be pityriasis folliculitis. This condition is caused by a organism called Malassezia, and it is common on oily skin such as the face, neck, upper arms, chest and back. This happens often in our humid climate, like Singapore. The spots are red, often the same size and pustular.
Treatment is simple topical cream. Chemical peels help as well.
Hope this helps!