Our 11 yo son has started to develop small spots or pimples on his scalp . They do not have pus but frequently have dried blood. Diameter is about 2 or 3 mm with a small hole in the center. I suspect insect bite but have not been able to ascertain a type. These appear only on the scalp, and nobody else seems to be affected. He is developing some conventional pimples and blackheads on his face. My wife is nearly panic stricken over this and is demanding I find a diagnosis now. His pediatrician did not know and another pediatrician didn t even bother to look closely. From this I assume it is not bed bugs or head lice , as these should have been instantly recognizable the doctors. We have taken close-up photos if this will help. Thank you, William Clapper