Hold on a minute...
Your girfriend put your hand/led your hand to her pants/in her pants.
She did?
She's the one that jumped away?
Good for her.
She should be asking you for YOUR forgiveness, asking forgiveness for leading you to a place where you shouldn't go.
You both are in this together, and you're not married yet so you're not the sole head of the house, head of the relationship (although preparation for that leadership may be good, if you believe in that sort of thing).
In my relationship, if we ever get to a point where we're in the heat of something and we do something that makes me uncomfortable, I'm gonna stop! And he figures out pretty quick to ask "What's wrong?" and then we talk about it. Sometimes there's guilt, usually not. Sometimes there's apologies.
Do I think what happened was wrong? Yeah.
You should keep your hand out of her pants, and she shouldn't lead you there. It's both of your faults.
Can you get over it? Yeah.
I think you need to sit down with God and ask Him where you were in the wrong. Sometimes, people aren't guilty about something because the Holy Spirit hasn't laid that conviction on their heart. Sometimes, people aren't guilty because they are blocking the Holy Spirit out. You can only decide where you're at with that and be honest with your girlfriend. If you aren't convicted, that's fine. That doesn't mean you can stick your hand in her pants again though. Sit down and talk with your girlfriend about what all y'all want your relationship to look like, physically (within those guidelines of "Christian values" she talked about (whatever that means)) in a God-honoring relationship. It doesn't need to be a "you should feel guilty" conversation, as much as a "ok, we did something wrong, what do we do now?" kind of conversation.
You're right though. It's hard to discern what is the right way to go, when the Bible doesn't explicitly say "Do not kiss your girlfriend for over 3 minutes continuously." and that makes things hard sometimes because you wish it would just lay things out explicitly. That's where prayer, a sensitive heart to the leading of God, and a heart of repentence and obedience comes in.
Best of luck with your relationship.