That's a really impressive work for a beginner!
Here are some suggestions. :)
line 1: "Pourquoi tremblent mes mains?" sounds very formal. You can use the "est-ce que" form like "Pourquoi est-ce que mes mains tremblent ?" instead
line 3: à tournant décisif → à un tournant décisif
2nd stanza, line 2: c'est maintenant → est maintenant
3rd stanza
line 1: bataille des polochons → bataille de polochons
line 4: à que → à qui
last line: s'écroule à la poussière → just "s'écroule" or "tombe en poussière". You can't say both (:
chorus
line 2: à la vie → according to the German words it's "à notre vie"
line 4: Je veux te donner tout toujours → I'd add a comma between "tout" and "toujours"
6th stanza: plein des violons → plein de violons
9th stanza
line 2: Tous → Toutes (it's "une seconde"). longes → longues (typo)
line 3: seulement → seul. rapide → rapidement
line 5: I would remove the "qui" because it sounds weird since the hand isn't mentioned after.
last line: et je pose cette question à toi → et je te pose cette question
11th stanza
line 3: rapide → rapidement
line 6: Quand on pose cette question à nous → Quand on nous pose cette question
And it's just a detail but in French there's a space before these punctuation marks: : ? ! ;
If you share my translations elsewhere, please link to this page/my profile and give me credit for my work. Corrections are always welcome.
Evander