Bleeding?

Nearly every time I masterbate, I start to bleed, it's not like my period, it feels like discharge except it's red. This happens when I rub my g-spot with my finger tips, I make sure my nails are short and when they are longer I don't play. This has been pissing me off so much because it's like I'm trying to please myself and sometimes calm down and then this happens and I just instantly get mad at my body. I don't know what's going on, people have said I must be scraping my g-spot but I honestly don't know how when my nails are short. I am not a virgin either, I don't have a cherry anymore.