Why The Foreskin Is Not Moving Back While Masturbating?

the head of my penis
Im 14 and of course I'm a male. so I h have extra skin and it was stuck to the rim of my head and so I'm still going through puberty and Ive been very...... I don't how to say it but this was like last year and I wanted to masturbate so bad but I couldn't cuz my extra skin and it would hurt when I would stroke it. but it looked like it was coming off in some spots and so I like separated it and it hurt and I started bleeding than the next day it was stuck again because the blood dried up. so I separated it again and it hurt and so now it left my these things but I don't know what they are? should I send a picture? please help.