Re: How to proceed with this girl....
A text message is in no way out of the blue. Like Poker said, she gave you her number, which is permission to carry the conversation to phone.
I would say though that the "game" you were trying to get her to play looked more like a dull and boring interaction designed to get meaning out of something. You should aim for fun, you should aim for flirty. If you aren't doing anything like this, there's no way you can get the girl.
For an opener, I would say if there's any nicknames the two of you share, use them. Just try to make the conversation fun and flirty from the get-go. Do that, and you will be just fine.
"There is no better than adversity. Every defeat, every heartbreak, every loss, contains its own seed, its own lesson on how to improve your performance the next time." - Malcolm X