Foreskin during puberty?

When I was about 10 years old, I started to pull my foreskin back. I was able to fully expose the glans, but noticed the foreskin was joined to the very back of the glans, all the way around. When I was about 14, I noticed that the join was beginning to rip and come away from the glans. This did not hurt and eventually it completely came apart. Is it normal for the foreskin to change like this during puberty?