character shaking when it moves

ok well i am working on a top down shooter i have made my character look at the mouse using screentoworld view and i made my camera follow my players x, and z axis but anytime my character moves parallel from the mouse it starts shaking I think its because it looks at the mouse an the mouse real world position is dependent on the cameras position which is, but i am not sure.

here is the playerscript the many backslashes showed other things I've tried

 gameObject.GetComponent<Rigidbody>().velocity = new Vector3(Input.GetAxisRaw("Horizontal")*movementspeed,0,Input.GetAxisRaw("Vertical")*movementspeed);  
 
         if (gameObject.GetComponent<Rigidbody> ().velocity.x != 0 && gameObject.GetComponent<Rigidbody> ().velocity.z != 0) {
             gameObject.GetComponent<Rigidbody>().velocity = new Vector3(Input.GetAxisRaw("Horizontal")*movementspeeddiag ,0,Input.GetAxisRaw("Vertical")*movementspeeddiag); 
         }
 
     // makes vector 3 type target equall to mouse position on pixial cordinates converted in to real world coordniates
         target = camera.ScreenToWorldPoint (new Vector3(Input.mousePosition.x,Input.mousePosition.y,camera.transform.position.y - transform.position.y)); 
 
         //Vector3 newtarget = target - transform.position;
 
         //lerptarget = Vector3.Lerp (transform.eulerAngles,newtarget, 100);
         // states the vector 3 values of target 
 
         // makes object local z face target and iniziates up axis 
 
         //Quaternion rotation = Quaternion.LookRotation (newtarget, Vector3.up); 
 
         //transform.eulerAngles = Vector3.up * Mathf.MoveTowardsAngle (transform.eulerAngles.y, rotation.eulerAngles.y, rotatespeed * Time.deltaTime);
         transform.LookAt (target,Vector3.up);

and camera script

     void LateUpdate(){
         position = new Vector3 (player.transform.position.x, 10, player.transform.position.z); 
         transform.position = position;
         //transform.localPosition = Vector3.Lerp (transform.position, position, speed *Time.deltaTime); 
         
         transform.eulerAngles = new Vector3 (90,0,0); 
     }