So back when I was 12, I slid down a ramp that was meant for trolley bags, and the ramp was made out of wood, at the end of the ramp was nothing. At the time, I saw my classmates sliding down that same ramp. I slid down the ramp, and it was pretty steep. I can't exactly measure it, but it was pretty steep. I slid down the ramp without my shoes on (I don't know why exactly, but I was being gutsy.) I slid down and then I slammed into the concrete wall in front of the ramp, I temporarily lost my voice and my lower back hurt like hell, the pain lasted around 3 - 4 weeks I guess. It hurt real bad but I didn't tell my parents. The pain went away and I assumed everything was okay. But I only noticed that my last growth spurt was only 3 inches, from 5'1 to 5'4, and I only grew 1 inch since then. I am 5'5 currently and I'm already 21.