Hi, I'm currently a junior in high school and I've been playing trumpet since the 5th grade. Going into high school I was switched from trumpet to French Horn so I could march Mellophone. So I have been playing French Horn for almost three years and needless to say, it completely destroyed any type of trumpet embouchure I would've developed before switching. I would rather play Trumpet in my high school band but I am too good at French Horn to let my director switch. I do plan on taking trumpet to college, recreationally of course, but I would like get better. My trumpet chops are pathetic. I can barely last 15 minutes and it's a bit or miss if I can play about a middle C. I just want to know if there is anything I can do to strengthen my chops and make progress on getting better, because I seem to be just getting worse the more I practice trumpet.