OK well I don't know how do describe this but ill try my best, me and my best friend were superclose and now we only have 1 class together, but I feel like something's different with her, its like I'm mad at her but I'm not, so I kind of not talking to her, and she keeps asking me if I'm mad at her and I say no cause I'm not, I don't think. But today her and her 2 friends said my name and glared at me, and I feel like I should be mad at her but I'm not sure I'm so confused right now, and I don't know what to do! I know this isn't the best description but I tried my best, so if you could please help me! I'm confused!

It sounds like with the changes to your schedules that you two are just spending less time together and might be growing apart a little. In close friendships this extra space between you can be awkward but that's normal. Just don't make a bigger deal out of it than it is (and don't respond to her or her new friends making trouble either) or you might end up causing a problem that doesn't need to be there.