Could Prolonged Periods Be Due To Weight Loss?

hello, it has been almost a year that i have been getting my menstrual cycle for almost 3 weeks out of the month...some months its very light other months like a normal period. But i am constantly bleeding, I currently weigh about 250, i previously weighed 310 but have been losing weight . i thought that maybe when i started to lose weight my period would regulate but i am getting worried that this is definitely making me anemic. or that it could be something much worse.