Hello,
From your symptoms, it can be a boil, an infected hair follicle, infected cyst or simply a hematoms formed due
to injury to the muscles. Application of mild corticosteroid cream and oral antiinflammatories like
ibuprofen/acetaminophen are helpful. Please keep the area clean and apply some warm compresses. Also wear
loose-fitting cotton clothing and use an antibacterial soap or mild soap like dove. Topical antibiotics such
as mupirocin or neomycin containing ointment are also useful. In case the symptoms persist then oral
antibiotics may be needed. Please consult a doctor in that case. I hope it helps. Take care and regards.