jxf

Ok so here is the background: my girlfriend and I haven't had sex at all (she is still a virgin) but we partake in plenty of foreplay and this past weekend she was over at my house and she basically gave me a "handy j" and I fingered her. I precame (I didnt come) and I put my junk away after we were finished for the moment. I got about 1/4 inch of precum on my index finger when I was putting it back in my jeans and i wiped it off on a napkin and we began making out for a while. My hands were all over her but nowhere inside or near her vagina and after about 30 minutes of that I resumed fingering her and called it quits for the night (I never came at all though). After everything she washed her hands and I did too, but I am really worried that the precome I had on the tip of my finger may have pregnated her.
Now here is my question (I would be grateful for a resourceful reply):
Is there any possibility that she could've gotten pregnant from dry precome that was exposed to the air for so long?