Thanks for the query.
I understand your concern.
According to your description the lump you mentioned might be abscess due to infected sweat gland or clogged sebaceous gland etc.
Sometimes rubbing of clothes, washing after bowel movements etc may provoke development of abscess. High blood sugar levels, decreased immunity may provoke these type of lesions.
As you are having severe pain, better to consult your doctor and get evaluated. In case of abscess you may need evacuation of pus. Antibiotics and analgesics may help in treating the lump.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.