Why does my girlfriend lower abdomen hurt after I fingered her? Did I poke her cervix? She is also sore in her vagina. I used two fingers this time.

Can't really tell... Can't really tell what is hurting nor why something is hurting, without talking to the person and doing an exam (maybe or maybe not related to the fingers), could be time to leave her alone to see if the symptoms quickly go away (and see the doctor if the symptoms stay around or worsen). Just using 2 fingers should not be a problem... It depends more on what the fingers do and how they do it.