Fainted after on my period?

Me & my boyyfriend were havin on my period when we were done there was blood everywhere on me on him & the bed we've had on my period before but I've never bled that much usually when we have on my period I barely bleed but this time there was a lot we decided to take a shower and I was fine until we got in the bathroom I looked in the shower and the water was all bloody I started feeling nauseous and dizzy I went in the shower and then I almost fainted I sat down in the shower and I couldn't see everything was blurry my boyfriend was sayin I was turnin purple & askin me what was wrong he turned the cold water on but I felt like I had to get out so he picked me up and I wobbled to the room layed down and the window was open so I was getting air then I was fine could it have been the sight of blood this has never happened to me before my period has also been a lot heavier lately though