Without examination, it is difficult to confirm a diagnosis, but from your description it looks like a mucocele. It is a rubbery, bubblelike painles swelling
or trauma. Usually it goes away on its own.But if it does not,then corticosteroid injections and surgical removal by scalpel or laser are done by a dermatologist. It then has to be differentiated from cold sores which are caused by herpes simplex 1 virus.
I sincerely hope that helps. Take care and please do keep me posted on how you are doing.