I`m really very bad in high notes and is another mouthpiece then a solution??

Lobke

first answer a few questions. How long have you been playing, what kind of mouthpice are you using now, and what size?

Well, i play 7 years now. I don`t really know what kind it is but that`s on it: Spezial Bruno Tilz. The size is 7C.

Stick to the popular brand mouthpieces of the same size such as Bach, Yamaha, or Shilke. No name brands or less popular types tend to have an angular rim that cuts into the lip. This might help you on some range and endurance, but a solid high register comes with good technique. Please find a teacher who knows a great deal about the trumpet embouchure and that`s where you`ll find real answers.