I've been playing the flute since 6 years old and now I'm 18. Before, I was only like playing around with this instrument but after learning more about it and classical music, I've decided that even though I'm not a professional player, I still wanna take the matter in a serious attitude (started around a year and a half ago), and here comes the problem.. I noticed that a lack of confidence has been lingering on me ever since. In recent years, I've been learning more about the right way to breathe, opening my throat, keep air support strong, etc. But I'd say I'm a rather easy-to-panic type of person. I'd get really anxious esp when i have to play solo within a group of people (band/ orchestra) or in front of an audience and sometimes even on lessons in front of my teacher (who I've been learning with for the past 9 years)
When I'm practicing alone, I'm able to remind myself to do all the right things, like, keep the throat open and try to project the sound through the head, not to tighten the lips, etc. But whenever I'm panicking, all of these will be gone, my throat becomes so tight that the air stream can't even flow smoothly, my lips becomes very tense and I lose my air support. All that's left is my anxiety and some notes waiting to be screwed up... I often end up blaming myself and giving myself a feeling that my playing always awfil

It's like the more I want myself the sound good and take the matter seriously, the worse I would sound and anxious I'll get. Sometimes it even feels like I've lost the confidence to play it in front of people even my family..
Is there any suggestions for me to boost my confidence and also to remedy my body's reaction towards my anxiety when I'm about to play?