Are you sure it's a scar and not something else?
If it is a scar, do you have a foreskin? Are you able to retract it? Does the scar going around the tip of your foreskin?
Have you torn your frenulum? That can cause scar tissue to grow.
You will need to see a doctor to know for sure what it is - no one can diagnose you online. Let us know what happens.
I have a foreskin, I can still retract my foreskin, the scar is white and is on the side of my frenulum its just very sensitive and can cause pain