Open Question: irregular period anyone have this problem?

I started having my period when I was 14 yrs old.. it was regular for about a year and then i stopped having them regularly I now only get a period maybe 3 times a year if lucky. So my question is does anyone else have this problem? I still get cramps and back pain every month I just dont get the period...Im worried that this will stop me from having children when Im ready! also my periods (when i get one) are very light to the point that i do not have to wear anything its almost just like spotting. and i will start my period then stop for a day or so then spot for a day then its over. any suggestions or just someone who has had this experience would be helpful I feel like im not even a woman! please help thanks