Hi Torico, I think that's how it should be. A print statement on the end of your function will only be called once. Also, when a functions run is finished all local variables (like your bullet variable) will be erased. If you want to constantly print the states of all bullets of your scene you could add them to a group (bullet.add_to_group("Bullets")) and then do something like
for bullet in get_tree().get_nodes_in_group("Bullets"):
print(bullet.name, " is at ", bullet.position.x)
Hop it helps. Feel free to ask more if not.