SOO TIRED

Ta
Im GETTING SOO TIRED of bleeding.. I didnt have a period for 46 days.. Bled for 28 days.. Stopped bleeding for 12 days.. And now im back bleeding (well spotting) again.. How does something like this just happen out of nowhere. Ive been to hospitals and doctors, they all say everything is fine.. Then why are my cycles like this? This is not fine or normal. Super heavy bleeding.. Some days huge clots.. Has anyone else experienced this?