(solved)Edit newly created projectile?

so basically, i'm using a procedure to spawn a projectile whenever i right click on an item.
it works, but it makes my projectile go up in a big arch, instead of shooting forward like an arrow.
like, if i'm looking straight forward, i'll go way up, before finally falling down and reaching my target, even though i'm not actually looking up.
how could i modify the projectile i've just created, to make it move in the right direction?
Edit: i ended up just using the "spawn entity with velocity" block instead of the "shoot arrow" block.