Hi,Dear Thanks for the query to HCM virtual Clinic. I studied your query with available details given in your query. I understood your health concerns. Cause for the lump on the chest- From the limited facts and limited story of your query, its very difficult to comment on the lump you had. Only with a history of bang which is questionable in itself,as you don t remember it,only possibility appears to be either - strong hit on the chest with skin blister pealing off the lump on the chest above breast, or it could be after the unnoticed bug bite with a blisters appearing on the lump which pealed on 2nd or 3rd day. Treatment would be -To consult a ER Surgeon and get the Xray / USG done to understand the bony or soft tissue status to understand the nature of the damage done by that unknown bite or bang/hit. -Antibiotic skin cream to protect any infection -Tab Motrin 1 x 2 times for reducing any inflammation or tissue edema. -light padded surgical dressing if need be as per advise from your doctor. -If no relief, Thrombophobe oint-reducing tissue hematoma,if need be. Don t Self-treat or medicate in your case as the case may go in to further complications. Hope this reply would resolve your query and would help you to plan treatment with your doctor. Hope this would relieve of your health concerns. Welcome for any further query in this regard before final suggestions are given in your query. Wishing you fast recovery.. Have a good day. Dr.Savaskar M.N. Senior Surgical Specialist