Also, Friday night (the night before an outbreak) I performed oral sex on my girlfriend. How substantial is the risk for her to contract genital herpes? She is unaware if she has the virus.
As far as infecting yourself somewhere else, no. You have antibodies that prevent this from happening.
Your girlfriend might be at risk. It depends on if she has the virus or not - at least half the adult population in the US has it, and most don't know it. 2/3 of the adult population globally does. If she has it already, even orally, she can't get it again.
If she doesn't have it, it's possible you were shedding the night before, and that increases her chances of getting it, but remember that you've had it the whole time you were together, and shedding, too, and she hasn't gotten it.
She can go to her doctor and ask for a type specific IgG blood test to find out, but the test misses 30% of hsv1 infections, so it wouldn't be definitive.
Try not to freak out. There's no way of quantifying the risk to her, but chances are good that she already has it, and you didn't have the full on outbreak yet.