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1.The possible cause in this case could be two, first is hair
follicle infection / inflammation, second
lymph nodal enlargement.
2.The inflammatory changes in the hair follicle with
nerve ending irritation can cause pain during the movements - it can be possible due to muscle movements.
3.The lymph nodal enlargement is seen in presence of any infection / inflammation / malignancy - it can be localised or systemic. So treat any illness if you are aware of.
4.The remedy in this case will be - do not disturb the lump,squeeze,compress,scratching the lump will cause complications and delay in heeling.
5.Apply anti inflammatory cream, clean the area with anti septic liquid, avoid shaving until complete healing, mean will trimmer will be better, avoid clothing which can cause rubbing in that area - use soft clothing. will be better in a week time. Good luck.
Hope i have answered your query,
any thing to ask do not hesitate to ask.
http://doctor.healthcaremagic.com/doctors/dr-ganesh/62888