When to kiss a girl at a movie?

Well I just graduated high school a few weeks ago, and theres this girl I've noticed since sophomore year (shes a year younger than me) whose drop dead gorgeous... I never had the courage to talk to her and half the time I wanted to, I was already in a relationship. So my bestfriend took me to a party on my birthday a few weeks ago and we some how ended up dancing together and she grinded on me and we ended up making out and almost hooking up (her parents were calling so I just took her home). As I gave her a ride home she put her number in my phone, and I finally texted her a few days ago (this is a few weeks later) and we ended up going on a double date with my bestfriend and his gf. We went movie hopping and during the movie I put my arm around her and she grabbed my hand and was like "sorry, I got a hand fetish" and held it through most of the movie. There were some points when she would scoot in really close to me and squeeze my hand tight and move her head really close to mine... I wasn't sure if that was a queue for me to kiss her or something but later during the movie I took her chin and went in and we made out a few times during the movie... I just wasn't sure if the timing was right.