you need to see your medical provider so you can have this skin lesion properly examined. many skin conditions will mimic an ingrown hair. it may not have been an ingrown hair at all but a sebaceous cyst (oil gland) or other common penile skin lesions. if your penis is important to you and i know that it is get it checked out. use a penis health creme called man1 man oil. it is made just for the penis skin and both treats and prevents all sorts of issues down there like rashes bumps spots dryness chafing etc. it's real good stuff. it is antibacterial as well so it will definitely help if you have some sort of an infection down there. you can get it online. good luck.
i had an ingrown hair on the shaft of my penis i got it out but its not really healing what can i do to help it. its been about 2 months ive stopped any kind of sexual activity