Girls are just fucking weird like that dude, don't take it personally! Maybe she just got out of a relationship, or wants to get back with her ex or something. Maybe she's got other pressing matters and just doesn't have time for dating. Maybe she's actually in a relationship and doesn't want to cheat, maybe she just decided she flat out doesn't like you. The more you think about it, the less good you do yourself! So don't worry about it
The best thing I could have suggested was to add her on facebook before she left, because she could see your name one day and think "hey, he was a great guy. Maybe I should say hello."
And good job on the kiss close, very smooth. You don't need tricks to kiss a girl for the first time, its something you just fucking DO. The more pressure you put on, the more likely its going to result in rejection, so you did great!
