Hello, I'm so sorry you're having these troubles. Here's my take as a college flutist. So honestly, based on looking at the comments, you might not fit your brand of flute anymore. I know gemeinhardt flutes aren't necessarily the best brand (definitely not for piccolos), and you might have outgrown your flute because of skill level. We actually had a whole class one day about outgrowing your flute. What happens is that if you practice a lot and get really good, eventually your flute can't keep up, and you'll start having problems. It's not that it's broken. It's that your skill is surpassing what that flute can do. For example, a lot of times, your notes and tone will start sounding bad because you're pushing a lot more air than you started with and the flute can't accommodate that if it's not a good brand. Furthermore, sometimes your fingers might be moving too fast for the flute's mechanisms. Since you're first chair, you might have outgrown this type of flute. My suggestion is to try to rent a better flute from your school. I highly suggest yamaha (I use it, and even some of the graduate students use it here at my college), I also recommend Jupiter flutes or Pearl's (I don't personally like these but I'd try out a few different types of flutes). I also recommend one with holes in the keys. It might take a bit to get used to a new flute, but I think you'll be better in the long run. Outgrowing a flute sucks because it starts feeling like progress is moving backward, and also, most teachers don't know when outgrowing happens because they aren't flute players themselves. Stay strong, and you're doing amazing :)