can not see any picture, bit more history will be helpful.

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Brief Answer:
Hair follicle infection

Detailed Answer:
Welcome to Health care magic.

Thank you for uploading the picture, its helpful.

The lesion / lump look like a hair follicle infection / inflammation with a mild collection of the pus within.

You can apply an anti inflammatory cream available over the counter on and around the lump, it should heal soon, as I don't feel like recommending you for antibiotic at this stage. At the same time please do not scratch / press the lesion as it may complicate and increase healing time. If its painful, analgesics can be taken.

Maintain local hygiene - you can clean the area with any antiseptic liquid before applying the cream.

Avoid any clothing that cause irritant to that area for a while, until it heals.

Don't worry, its not some thing you have to worry ( its localised infection). If no improvement observed in two days - then you may have to see your GP and get a course of antibiotic treatment.

Hope it helps you. Wish you a good health.
Anything to ask ? do not hesitate. Thank you.

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