I remember way back when I first started jacking off. I started late, at 18, for whatever reason. I distinctly remember using a ruler a few times on my cock, and it was over a foot long. It was 13 or 15 inches, depending on the day, my mood, etc. Over the last few years I've shrank a lot, I have no idea why. Now i'm down to 7-9 inches. Any ideas why this happened to me? My diet and exercise has only greatly improved over the last few years, that's the only big change in my life really so far.