Pregnancy?

Im extreamly worried. Im 15 and It seems a little early to even be talking about kids. Which I don't want until im older, But Ive just been worried about not being able to have kids.  No one told me i couldn't have kids. But my period tends to skip months, or comes extreamly late. I just wanted to know if thats normal. First time i got my period was when i was 13 so im not really sure.