What's My Problem Please Help?

i dont feel sick or anything like that but my period hasnt come in 4 to 6 months and for some reason i keep having headaches but no vomiting or weakness but for some reason my stomach does like this weird rumbling and i went to the doctor and she said there was nothing wrong with my hormones and there's no way i'm pregnant but also my mother had thyroid disease and i think that's hereditary what is most likely wrong with me?Could it be thyroid or pcos?