About three months ago I had wonderful accuracy on the notes I played. If they were fast, they'd be a little out of tune, but I thought that much was self-explanatory. Starting about two months ago, though, I've been having a lot more trouble tuning to the band, holding a note at the same frequency for over a few seconds, and general accuracy with anything I played. My Private Lesson teacher said it's probably just a weird trumpet thing and to clean out my horn, or that it'll blow over eventually, but both of my school's directors agree that I'm actually ready for a step-up horn. I'm playing the yahama advantage that I got in 5th grade-which is a beginner horn- and they think I should look into buying a strad if I wanted to start getting serious in my musical career. The only problem: My family can't afford buying a $3,000 anything, and my high-school part time minimum wage job isn't going to be able to support it. Would anybody have any suggestions as to helping out my accuracy&intonation?