Don’t stress, there’s nothing wrong with you. Similar experience; around hitting puberty my penis continued to grow but my foreskin pretty did not. I think it was a combination of factors; genetics/physiology (kind of a family joke that men in my family tend to have prominent penis heads), the fact that my dad was insistent upon my pulling my foreskin back a lot for hygienic/medical purposes and because I was apparently wearing my underwear tighter than I needed to (didn’t discover the joy of boxers til college.) My foreskin hasn’t covered my penis head in nearly 20 years and pretty much anyone who sees it (including doctors) assumes I’m circumcised. So far it hasn’t given me any problems. If you’re not in pain, don’t worry about it, there’s nothing wrong w you.