Hello. Thank you for writing to us at healthcaremagic I suggest a possibility of a bacterial soft tissue infection, most likely a furuncle or a boil. The fact that it is tender and has increased in size overnight are points in favor of it. The infection usually gains entry through the hair follicle. If I was the treating doctor I would suggest you to take a course of an Oral antibiotic for a week. My choice of an oral antibiotic would be either cloxacillin or cephalexin for a week. Oral antibiotics are prescription drugs therefore I suggest you talk to your local practitioner for the needful. Topically you may use an OTC topical antibacterial e.g 2% mupirocin ointment, twice daily. An OTC anti-inflammatory e.g ibuprofen will provide symptomatic relief from pain and swelling. Don t pop or try to squeeze it. Regards