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1.As you said the possible cause of the lump on the head with soreness and pain suggestive of the hair follicular infection with collection within.
2.The treatment in tho case would be antibiotic course with symptomatic treatment.
3.In complicated case and which are not responding on the treatment - it should be
incision and drainage followed by the antibiotic course.
4.As a remedy do not squeeze, press,scratch the lesion as you will only complicate the condition. Clean with an antiseptic liquid.
5.So, i would suggest to see your GP, gat examined and needful treatment good luck.
Hope i have answered your query,
any thing to ask do not hesitate to ask.
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