Are scars unnattractive?

Hello! I am a teenage girl, and I have noticeable scar right in the middle of my chest-- its almost perfectly round, and is a little bigger than the eraser on the tip of a pencil. It also bumps up from the rest of my skin, which makes it more noticeable. I am very self-conscious of it, and I always wear shirts that cover it up. I know that no one finds scars attractive, but I was wondering just how much of a turn-off they really are. I'm always afraid that once guys see me with my shirt off, they'll be repulsed or something. Any comments or advice? I'd appreciate anything you have to say....