Hpv bumps from masterbating?

I am 14 years old and I started masturbating 2 years ago. I hear that masturbation is safe with no side effects--in theory.
First of all, there is a rumor that excessive masturbation at a young age shortens the male organ due to Testoserone depletion. I confirm this statement whereas mine has shrunk from 6inches in 7th grade to 5inches for freshman year.
Second of all, 3 months after I started masturbating I have developed bumps on my scrotum. I say I have had no sexual contact with anyone, I repeat I have had no sexual contact with anyone. I hear that HPV is a person to person STD only. These bumps have been growing and every part of it matches the description of HPV on the web. Pictures(regretfully, im desperate for info.), descriptions, everything. I have not been to the doctor yet concerning this issue but I will for my next physical. I appreciate any reply concerning this condition. Thanks

By the way, If you are thinking about masterbating it is highly addictive and could get you started in watching porn or posing for pornography. Religously it is immoral. I recomend waiting until older age or marrige for sexual activity for it avoids many, many harmful complications. Please make use of my advice.