I had tight foreskin (phimosis). i couldn't get the foreskin behind the glans. My foreskin orifice diameter was around 0,5 cm.
After 10 months of everyday stretching I managed to stretch the foreskin so that now I'm able to put a cylindrical object with a diameter of 6 cm + 8 fingers inside the foreskin. That's a great improvement.
Now, foreskin pulls back behind the glans when erect but it doesn't feel comfortable. I feel some discomfort and this causes me to lose erection.
Should I stretch further?
What is a typical diameter of normal foreskin?
Could someone measure it up? :-)
It sounds as though your foreskin automatically pull back behind your glans when your penis is erect and that you don't like that. You may stretch your foreskin by tugging on it to make it longer. That way it will stay forward when it grows.
Search for "foreskin restoration" on line for tips on stretching your foreskin.