Velocity, my dude, is not everything. I speak first hand. I'm 15, 5'10", 140 lbs and a freshman at Hillsborough HS. I've been a closer on my baseball team for a while, but I just got converted to a starter within the past year. When I was 10 and 11, I was still the closer, so I didn't pitch a ton. Instead, I went home with my dad and followed a throwing program (although not correctly). I thought it was a good idea to go all out everytime I threw, so I longtossed and tried to strengthen my arm. Looking back on it, a very dumb choice. At 15, now, I still throw very hard for my stature (77-79 mph fastball on the gun) and have a nice 11-5 curveball and "Vulcan changeup." However, I face the risk of Tommy John since my UCL is quite swollen right now. Hopefully I'll just need a cortisone shot, but I was told not to throw for at least 4 months. So seriously, do NOT overthrow, and do not worry about velo all the time. It should come naturally. I'd focus on developing strong offspeed and good fastball movement. And a tip I can give you for velocity without putting tons of stress on your arm is to literally pitch from 75-80 feet before starting a game. I tried this last year and lit up radar guns once I got into the game. It makes 60 feet look like 40 once you get there. Good luck man and to everyone reading.