I am heading into my sophomore year of high school (10th grade). I decided that I would increase my range during the summer as I am moving up to first trumpet in marching band and lead in jazz. I have been doing the 19/30's exercise when I can for about a month now. I was pleased with my progress until about a week ago. I can consistently play strong, full notes up to Eb above the staff (progress for me, having struggles to hit high C earlier this year) but that all changes when I get to E. Even when I scale up chromatically I just get air on High E. I would be happy if it even just barely squeaked out. But there's no sound at all beyond that of air going through my horn. Any help is greatly obliged.