Hello,
Welcome to the ehealthforum and I am really glad to help you out. Your concern is regarding the small growth on the testis. The first possibility is of an irritated hair follicle or infected hair follicle. Folliculitis starts when hair follicles are damaged by friction from clothing or blockage of the follicle.
The second possibility is of any cyst like sebaceous cyst which is a bengin lesion that has to be surgically excised. The third possibility is of a benign growth like angiokeratoma or some benign skin growth like seborrheic keratosis. The fourth possibility is of a genital wart which presents as brownish, rough cauliflower like growth. The last possibility( although less likely) is of herpetic lesion. Most individuals have no or only minimal signs or symptoms from HSV-1 or HSV-2 infection. When signs do occur, they typically appear as one or more blisters on or around the genitals or rectum.
i suggest you to get it examined from a dermatologist as treatment is specific for all.
I sincerely hope that helps. Take care and regards.