I think you meant "stuck" at 2/3, right?
Is this something new? Have you been able to pull it back all the way in the past? If so, it may just be some dried smegma acting like glue.
Some say it's normal for the foreskin to be stuck to the glans and begin separating at about your age, so that may be the strange feelings you are having. I wouldn't worry about it, just keep pulling it back to check on it.
Mine was never stuck but that may be due to the fact that my mother's doctor told her to pull it back to clean under it when I was born. I have no way to know what happened at that time. Maybe he separated it before he gave me to her or maybe mine was just never stuck anyway.
I'm pretty sure that her and later me pulling it back all the way to clean under it has kept it loose and free and I have had a lot of fun pulling it back.