I’m 16 and have been having my period since I was roughly 12 and a half. I have always had REALLY irregular periods like there a months where I don’t have a period. But in the past few months I have been having really bad lower abdominal pain and every time I do a pee test or go to the doctors I never test positive for having any sign of an infection. At the moment I haven’t had my period in three months but there is absolutely no chance of me being pregnant. What is wrong with me and will I have fertility problems???