Is my penis too big for me?

This sounds sketchy but it seems unhealthy. I have a 13 inch penis and I am 15. I am 100% white. I'm 5'9 160 pounds. It is rather large in correspondent to my body and can be extremely uncomfortable to hide when those surprise woodys come around. I have had one girl touch it when making out and she was grossed out by the size. My friends say they have about 6-7". Is this normal? Should I possibly have it shrunk if thats possible?