Hello,

Thanks for posting your query. From the symptoms that you have described, It will be very helpful for me in understanding your condition better if you could answer some of these questions:
1)     Is the lump painful or is it itchy?
2)     Does it drain any white sebum like discharge?
3)     Does it have any redness or warmth?

Such kind of lump can be due to insect bite or an infected hair follicle causing a boil. Apply warm compresses on the bump and keep the area clean with topical antiseptics. You can apply a topical antibiotic cream like Neosporin or Bactroban. Also wear cotton clothes.

Hope this answers your query. If you have additional questions or follow up queries then please do not hesitate in writing to us. I will be happy to answer your queries.

Wishing you good health.     
Regards.

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