brown blood for months

i’m 18 my period has always been normal kinda heavy and my cramps would get pretty bad but the past 2 years it’s been really irregular and now the past 5 months it’s been barely coming and i’ve had like no period cramps which isn’t common for me and now i’ve had brown blood for the past like 3 months not sure how long it’s actually been and my period never comes anymore last period i had was a month ago and that was the first actual cycle in months

i don’t take any birth control nor am i sexually active i’ve been reading some stuff and giving myself anxiety over this does anyone have any answers to why this is happening