Not shooting in desired direction

Hi everyone,

I have a topdown view in my game, for that I rotated my cam 90° around the X axis. Now I have a "shooting" script.

 GameObject projectile = (GameObject)Instantiate(Resources.Load("projectile"),spawn.position,Quaternion.identity);
                 projectile.transform.LookAt(cursor);
                 projectile.rigidbody.AddForce(transform.forward* bulletSpeed * Time.deltaTime);
                 Destroy(projectile,5f);

The Problem is, my projectile is not moving to my desired direction "forward" its moving to the north, but my "gun" is facing to the right. I think that is because of my camera rotating right? So how do I recalculate the direction ? I also tried TransformDirection and so much more nothing works for me:/

THanks in advance