Question about my girlfriend....I fingered her for the first time and now her vagina burns....help?

Ok so today I fingered my girlfriend for the first time. We did it about....4 times. The first time, I washed my hands. The second time wasn't long after but I washed my hands not long before then. The third time I forgot to but my hands were too dirty. The fourth time, I washed my hands right when I remembered to.....which was pretty early in. My fingers that I used were a little rough, the cuticle is torn a little. (She went pee a few times in between) Now I'm concerned because she says her vagina burns a little. It was her first time having something that deep in her and she is a virgin so do you think that has something to do with it? Did I scratch her? Might I have given her a urinary infection =/? I'm really hoping it's just a first time thing. Thank you very much.