Ok I got this situation I need help with?

So this Girl iv been talking to I like alot right. we kicked it a couple of times and kissed or what not. So if I ask her to kick it. its not always a yes. she say because she has tests and study because she becoming a nurse. sure understandable. so its been like two months since we hung out. she texts me and asks to do something with her. I say sure. I told her lucky its not a day I had my bball league or she would be out of luck. she texted back. "You would have quit your league to come with me. lol" now maybe she was joking sure. but maybe not. so i gets to thinking. Im a yes man! I say yeah to whatever she wants to do. tho if i did have bball she wouldve have gotten a no. but still. problem is there is not another chick that can get this much attention from me. I have alot of girls I talk to but this one got me on the ropes. something about her. she so hard to get I have to pursue and pursue some more. No girl ever made it this hard to obtain. so my question is! should I stop with this yes stuff? should I call her the day we suppose to kick it and say sorry something came up? because she got all the power right now. I cant stand it. but at the same time. I can. its crazy! help a playa out!