How To Treat Tight Foreskin?

Hello Doctor,iam a student of 19 yrs of age... 1.) the foreskin of my penis doesnt move back when i get erected , i thought that it goes back when u get erected, will there be any pain / problem in my future if i have sex ? 2.) the size of my penis is very small, i have checked d average size of a penis but mine is below average, sud i undergo some operation or treatment for my problems ?