What caused me to bleed when I purged?

Okay I was just wondering..I purged for the first/and last time..awhile ago and I was using a toothbrush. Sometimes hitting the back of my throat with it. But anyway, when I was done and pulled my toothbrush out, there was blood on it. Could it of been from hitting the back of my throat or do you think blood came up? Just wondering..curious. No big deal to moi,don't plan on doing it again.Thanks.