I like this girl, but I'm unsure of how she feels towards me? 10 points!?

Hey

Basically I've begun to really like this girl. We've been talking for about three weeks, and I generally walk her to class daily. She doesn't seem annoyed with me, and she seems interested. We text daily, and she'll text me "hey :)" in the mornings if she falls asleep. We haven't hung out of school yet. For the past two weekends she was busy with other things and I let it slide. This weekend I figured I'd you know make sure we hang out, and if she was busy then maybe I'd consider shes just blowing me off. Anyways, today and I met up w/ her in the hall and walked her to class. On the way I figured I just tell her that I like her. I said "hey listen I think youre really cute, and I think I've began to start liking you. I was wondering if this Saturday you were free, because I'd really like to hangout w/ you. " I said something like that. Anyways, she replied "oh yeah sure I'll hang out with you, I'll let you know". I figured she'd least smile or say aww, you know, be flattered. That sort of downed my mood but whatever least I did it. Anyways, we were texting throughout the day and I asked her if shed like to meet up later in school. She said she had a lot of testing to be done, which I I feel is just an excuse. Reason being, one period she had lunch and the other she had gym. Lunch I saw her in the hall walking with her friends, so maybe she just wanted to hang with her friends. But yeah, I feel she wasn't "packed" with testing. She's in 9th, and I'm in 10th, but I know the 9th grade curriculum, she wouldn't have that many finals as far as I know. That made me feel she blew me off, as well her saying she was busy other days when I asked her to hang. I guess that's it, I mean did she just text me "soo whats up :)?" so I don't think shes creeped out? She still seems to want to talk to me, but I really don't know. Maybe she just wants to be friends? I'm not holding any high hopes that she'll say shes free on Saturday. Do you think I should bring that up? Tell her that I feel like shes blowing me off, and that if that's the case I don't wanna annoy her. Though if I annoy her, why the hell would she bother to text me and seem interested in talking to me? Maybe I should just drop this eh?

Any Advice?

Thank you for reading!