I agree with the other posters...it's just your cervix, where your period comes from. Look up female reproductive organs on google and the second link down gives pictures and explanations as to what everything is.
It's just your cervix, there is absolutely nothing wrong :)
That is where your period comes from. It's the opening of the cervix. I hated health class at school. They just handed us "pads and tampons" and never really explained anything, of what was in there or the whole process. I remember being 11/12 wondering what in the world I would do with a tampon. lol.