Mouvement issue with mouse input.

Okay so for being transparent i follow the brackeys tutorial for fps camera (I'm not creating a fps but the camera is the same). At the beginning it works fine. But after more script added to my project something strange happened. When i start the game, if i dont touch to my keyboard, the mouse(camera) movement works fine. But if a touch for exemple to the "W" key for go forward if i move my mouse my player go realy fast forward or backward (move on left and right). For sum up my issue, if a move my mouse, my player go outside of map, his position make no sens, and if i don't touch the mouse, the movement works fine. (Sorry for my english).

Script : Player controller

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class PlayerController : MonoBehaviour
 {
     [Header("Move Settings")]
     public float MoveSpeed = 5f;
     public float JumpHeight = 20f;
     [Space]
     public LayerMask GroundLayerMask;
     public Transform GroundCheck;
     //
     private bool isGrounded;
     private CharacterController controller;
     private Vector3 velocity;
     private float gravity = -20f;
     //public Camera Cam;
     int nbJump = 0;
 
     void Start()
     {
         Cursor.lockState = CursorLockMode.Locked;
         controller = GetComponent<CharacterController>();
         Cursor.visible = false;
     }
 
     void Update()
     {
         if (Input.GetKey(KeyCode.LeftShift))
             run();
         else
             walk();
         jump();
     }
     #region jump
     void jump()
     {
         isGrounded = Physics.CheckSphere(GroundCheck.position, 1f, GroundLayerMask);
         if (isGrounded)
             nbJump = 0;
         if (Input.GetKeyDown(KeyCode.Space) && isGrounded)
         {
             velocity.y = Mathf.Sqrt(JumpHeight * gravity * -2);
             nbJump = 1;
         }
         if (nbJump < 2)
         {
             if (Input.GetKeyDown(KeyCode.Space))
             {
                 velocity.y = Mathf.Sqrt(JumpHeight * gravity * -2);
                 nbJump = 2;
             }
         }
     }
     #endregion
 
     #region walk & run
     private void walk()
     {
         float x = Input.GetAxis("Horizontal");
         float y = Input.GetAxis("Vertical");
         Vector3 move = transform.right * x + transform.forward * y;
         controller.Move(move * MoveSpeed * Time.deltaTime);
         controller.Move(velocity * Time.deltaTime);
         velocity.y += gravity * Time.deltaTime;
     }
 
     private void run()
     {
         float x = Input.GetAxis("Horizontal");
         float y = Input.GetAxis("Vertical");
         //Cam.fieldOfView = Mathf.Lerp(120f, 100f, Time.deltaTime);
         Vector3 move = transform.right * x + transform.forward * y;
         controller.Move(move * (MoveSpeed * 2f) * Time.deltaTime);
         controller.Move(velocity * Time.deltaTime);
         velocity.y += gravity * Time.deltaTime;
     }
     #endregion
 }

CameraScript :

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class PlayerLook : MonoBehaviour
 {
     [Header("Player Settings")]
     public float mouseSensitivity = 90.0f;
     public Transform PlayerObject;
 
     float xRotation = 0f;
 
     void Start ()
     {
         Cursor.visible = false;
         Cursor.lockState = CursorLockMode.Locked;
     }
 
     void Update ()
     {
         float mouseX = Input.GetAxis("Mouse X") * mouseSensitivity * Time.deltaTime;
         float mouseY = Input.GetAxis("Mouse Y") * mouseSensitivity * Time.deltaTime;
 
         xRotation -= mouseY;
         xRotation = Mathf.Clamp(xRotation, -90f, 90f);
 
         transform.localRotation = Quaternion.Euler(xRotation, 0f, 0f);
         PlayerObject.Rotate(Vector3.up * mouseX);
     }
 }