Small skin coloured bump on the scalp could be just due to blockage of the hair follicle. So whatever secretions are there remaining inside and you get a skin coloured bump. So when there is no itching, redness or nothing, if you scratch it can get inflamed and get secondarily infected and then you can have a pustule. So if it is just a skin coloured bump then you need not bother. Sometimes a skin coloured bump with rough surface could indicate that there is a viral infection. In some conditions like verucca vulgaris you can get a skin coloured bump initially and which later becomes rough on the surface. So it is always better to consult a dermatologist and get things sorted out.
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