Period for 14 days??

so last month I was really late on period (21 days actually) and I haven’t had sex so I wasn’t concerned about if I was pregnant or not but on June 8th my period finally came. It’s not June 21 and I’m STILL bleeding. I’ve been to the hospital but they couldn’t help me. I’m only a child so this is all kinda new to me. I’m 14 but I’ve had my period since I was 9 and this has never happened