At what point should I be worried? Tmi

So this is like period day 9 I thought it was ending because the blood turned brown like old blood again and the flow slowed down. But I went to he bathroom and wiped and saw a bunch of bright red blood and there's a lot of it and it's just pouring out when I go pee. I don't understand why I'm bleeding so much right now. This has never happened to me. It's kind of worrisome.