Red Testicle Bumps.

Ever since i was 10, i started have red swollen bump on my epididymis. its about half centimeter. Reddish/pinkish. I can't bust it. It doesn't hurt when i don't squeeze it, but when i do it hurt.Sometime when it turn purplish on my asian tone skin. It do look like a cauliflower but however i don't think its Genital wart because it doesn't grow nor spread. I'm 16 now. so 6 years it didn't move or spread. Also, when i was young. i sorta over-masturbated myself . That was when i started to see these lumps/bumps. But when i research, over masturbation doesn't lead to lumps or bump. I only have 6 or 7 bumps. Not a lot. When i was smaller my friends we use to drink from the same water bottle when we have fun. I think i have STD..then i think i don't. : ( PLease Help.