What Causes Bleeding And Foul Smell While Fingering?

Hhey, see my gf and i were having a great time the other day.. i was using my fingers then,(2 at that) but when i pulled em out.. i noticed blood.. i was freakin out, but she said she didn't feel any pain or what not. it had this unpleasant smell too.. kinda strong. what to do?.. what's the deal with that?..