What Causes A Light Bleeding After Masturbation?

Hello. I am a 19 yr old female, and recently I masturbated internally, and when I was done, I notcied some slight bleeding. I wiped and saw a small blood clot, bright red, come out. My vagina feels a bit irritated but does not hurt, however I am still bleeding, not profusely though. I am a virgin otherwise, so I'm not quite sure what is happening. This is not the first time I've masturbated so I don't think it's hymen related. Can you help? Thank you...