So let me get this straight.
You and your girlfriend hit a snag in your relationship.
And, instead of discussing it like adults, you thought the best way to handle it was to play head games?
Uh huh.
May I ask why you're surprised your actions caused things to blow up in your face?
If you want a shot at fixing this, I suggest you be honest with your girlfriend about your actions as well as your motivations.
Then, presuming she still has an interest in you, the two of you can start back at Square One and begin to forge a relationship.
But be advised - if she was already having some doubts, she's not going to want to work to improve what you've got any longer. You will have to be completely open and honest with her and trust she is doing the same with you - and even then, you might not know until the roof falls in upon you.
I wish you good luck and have one final piece of advice: Games are for fun - not for relationships.
If it turns out that this relationship is over, please learn from your mistakes.