Style struggle

When I look around in my high school, I see so many people with such great unique styles and I always tell myself that I have to make my own style as well. But here's the problem. I like so many things from different styles, like I love shirts and jeans, but I also love skater skirts and dresses and floral pattern. I love cute graphic tops and I also want to dress more elegant. So when I come to the shopping mall I firstly don't even know to which store I should go. Besides, I go shopping on such rare occasions, usually when I really need something (because of the ''never enough time struggle'') , so I don't really have much already chosen. The other thing is that I'm not confident enough, to buy some pieces. My clothes are really very plain, jeans, lots of sweaters (I got way too many Christmasy ones) and actually just a few things that I actually like. That's probably also because I change my taste in clothes so quickly that I shouldn't be allowed to buy more than 2 things at once. That's what makes shopping even harder. I never really know if I should buy something, so I end up trying on for hours and then buying two things or nothing at all. My mum says that I am a very unsatisfied person and that I never like anything, but that's not completely true! I'm just not sure anymore what I like. If I see a girl what an outfit that I really love, I'd feel like a copy cat if I bought something similar. I kind of envy girls who start wearing something cute and it later becomes so popular, that when I notice it, so many people are already wearing it. Then I kind of don't want to have it anymore, because how can stay unique that way? Also, like I mentioned before, my style is very plain, nothing bold, so I think that if I started wearing different clothes people would give all sorts of mean comments, which I couldn't bear. I know, I'm a little bit pathetic. I hope I'm not the only one feeling this way. If you have any advice or tip that would help me, I'd be very happy to hear it. Thank you so much for reading this weird post, haha. :)
                                                                  xoxo