I hate having speech impairment

I have speech impairment, I can't pronounce many letters correctly. In my native language the letters I can't pronounce are used in words very often. I recently went to a new school and I'm so embarrassed because of it. In my old school everyone already got used to it and nobody paid attention to it but in the new school none of the teachers cared enough to acknowledge it. In my first ever english class in the new school my teacher asked me to say "she" which I can't properly pronounce so I just said it the best I can. My teacher acted confused and just said "Wait, I don't think we understand each other" so in front of my whole new class I had to say I have speech impairment which she should be aware of because I informed the school of it because I also have dyslexia so teachers are obligated to acknowledge it because I need to have easier tests and more time. I felt so embarrassed, since then I can't bring myself to speak out loudly in any class. My new friends also seem to find it funny, they ask me to say some words I can't pronounce while laughing. I heard these "jokes" so many times in my life that I genuinely jus want to cry whenever I hear it. I'm so tired of it, I try my best to speak correctly but it's difficult. The only two teachers who seem to actually acknowledge it is my Spanish teacher and physics. I also want to say that There is another guy in my class who has Dysgraphia which causes him to have trouble writing and every teacher is aware of it. If they can acknowledge this then why did they decide to ignore my problems