Irregular cycles and fertility?

Okay guys, so I'm 19, and I've always had super irregular periods. Like impossible to chart periods. And I really want to have kids one day, but I'm so afraid that I'll go to the doctor and they'll tell me that I'm infertile. I know irregular periods are more common than one would think, but mine are just.. like I had to go to the ER once because I was bleeding through a super plus tampon and a nighttime pad within like 15 minutes. So if there are any words of encouragement or wisdom that you could give me I would greatly appreciate it!