place: My friends car

Late at night, my friend is driving a car and I'm next to a cute girl in the back seat.
The car is full, so i sit next to her with my thigh pressed against hers.
We've met a couple of times before, but never really spoken with each other.
I engage her in casual conversation, making sure i keep my leg up against hers as incidental kino. I keep eye contact with her, and sometimes she looks at me a little bit to long at a time. I take that as she's showing interest in me.
After a while she says:
-Damn, I'm shaking of cold!
I place the back of my hand against her thigh,(as a class 2 kino) not the palm since i felt that would be perverted somehow, and i was afraid she would be scared.
I say that she indeed is shaking, and i ask her if she wants a beer. (this car trip was a beer run)
She laughs and says that she can't get drunk and party in the pants she's wearing. Pointing to her red sport pants.
I reply by saying that she would simply have to take them of if that was the case.
She laughed and said that she would do that later.

At this point i thought to myself: Fuck Yea, I'm In!!':twisted:'

But what happened after this was that she turned to talk to the other person next to her.
I ignored her, closed off my body language toward her and turned to look out the window.
After a minute or so she poked my shoulder and talked to me, i opened again.
Joking a lot, throwing her negs. But after a while, she turned away again for no apparent reason. I ignored her again, but she didn't do anything this time. I tried to engage her again, but this time, i was the one who was frozen out. I didn't wanna come on to her like i was desperate, that would not lead anywhere i think....

I felt like i had lost, my confidence ran away and i sat silent for the remaining of the trip.

What did i do wrong, any pointers? Did i go too slowly? should i have shown more sexual interest for her?

All answers are welcome