I m 19 and had my first period at 13. I ve never been regular (sometimes for a couple months, but never fully), but I usually had the same kind of flow. Heavy, then light, 3 days. I haven t had my period since November, but I ve had very light spotting a couple times these past 3 months (one day, one time, but never an actual flow). I m not pregnant. So why has it changed? My older sister has PCOS, and my mom has Hashimotos. Does it have something to do with that?