You have some very wise friends, and they are right it could give you some very bad problems, and there are lots of things you dont know about yet, to much masterbating could also ruin you future sex life, so if you dont wont to with a girl and cant get it up, then just cut it back to as little as possable, just remember we come as a set, 1 man 1 p***s and if you break it you wont get another one, just remember the little head leads the big head, and if yours is broke then no sex life, no wife, no life.
Good Luck
Don't think masterbating is bad! It releases endorphins and its actually good and has been proven to reduce the risk of prostate cancer! However just don't get addicted to it so limit yourself to a few times a week so it's still a fun treat when you get to do it.
It isn't a really bad thing, but it can cause you to become a bit 'addicted' to it which could become embarrassing when around others. One way to stop it is to do something right before you go to bed, like playing your X-box or something. I'm a 16 yr old girl.
Not gonna lie to ya, most boys at your age masturbate A LOT. But when I look at other questions I've been asked, they're usually older guys saying they've got problems keeping it up etc etc and they think it's caused by the fact they masturbated a lot when they were younger. So maybe it's time to calm it down a bit haha :Pxo