A teacher is being really mean?

Hi, ive been playing guitar for a while so Im trying out for the talent show at my school. The auditions were todayand The teacher was being really rude. Just because she's a teacher she thinks that she knows everythign adn the students cant ever correct her. There are 2 music teachers at my school. Once when my teacher had to visit her sickmother, we started a new song, and there was a note I couldnt play on the sax.. she told me to pinch the reed harder and even when i did, it didnt work and i told her i was pinching it as hard asi can but she started yelling and saying that i wasnt when she wouldnt really know. plus she doesnt even teach us anything she just sits there drinking her coffee the whole time. so today there were about 5 people auditioning for instruments and after everyone else finished playing she said it was so beautiful and she loved it but after i played she just said nothing. I think i actually did pretty good because i practiced a long time and after I played i saw the look on her face and shel ooked really mad. Idk why she would do that because my real teacher said i was good. I don't mean to sound like I think im the best or anything but my friends told me she is probably a bit jealous of me. then after everybody left she told me to stay and she said that she doesnt know if i should play in the talent show and when i asked why she started yelling at me and said why are you questioning me. She said she wil " think about it".. tomorrow is the 2nd audition for ppl who missed it and she told me to come again so she can decide but now that she hurt my feelings i dont even feel like going anymore. wat should i do? :( thanks so much!