I have never noticed this before but after some sexual activity (not intercourse) I later noticed an engorged vein or something of that sort in my left testicle and only a slight bit of discomfort. What could this be? i've looked up some information and i'm not sure if it's really a problem or if I should tell my parents or go to a doctor or something. As it's my sex organ I'm a little nervous. If someone could help me with this, that would be excellent, thank you.