This depends on 2 things:-
1. The manufactured key of your trumpet, i.e. trumpet in B flat/ or A/ or C (or sometimes D)
2. The key of the original music, and pitch of the notes.
If the notes are too high to play on trumpet, you will have to transpose the notes down - this is known as "Transposition" and is covered in Grade 5 Theory of Music, Associated Board.
If you do not require a piano accompaniment, and the notes are just played 'solo' then you will need to transpose every note down - however in doing so, you will change the key. You must also make sure the interval between each note is the same. So for example, if your music is in they key of G major (having F sharp as a key signature), if you move every note down a tone (major 2nd), you you will then be in F major. This will affect certain notes in the scale - so if you blow a 'C' in the original music, this will become 'B flat' in the tranposed version.
If just the 'odd' high note cannot be reached, then try a tone lower.
If you have any problems - email /attach the music so I can see it, and I will transpose it.
However please note that when you transpose music 'down' - the new key and key signature may be alot different and more difficult to read. I think the reason your music doesn't sound correct is that you haven't got the relationship between tones and semitones correct.
Hope that helps.....
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