very laggy game and can't not flip chracter: 2d game C# script

pls help there are a few things wrong with my game pls help

  1. my game is VERY VERY laggy
  2. this is the main one my game character won’t flip so my charater won’t change direction when I press backwards he just walks backwwards I check the script and everything seems fine. here is the errors

1.NullReferenceException: Object reference not set to an instance of an object
PlatformerCharacter2D.Flip () (at Assets/Sample Assets/2D/Scripts/PlatformerCharacter2D.cs:85)

2.PlatformerCharacter2D.Move (Single move, Boolean crouch, Boolean jump) (at Assets/Sample Assets/2D/Scripts/PlatformerCharacter2D.cs:60)

3.Platformer2DUserControl.FixedUpdate () (at Assets/Sample Assets/2D/Scripts/Platformer2DUserControl.cs:37)

here are the 2 scripts I use C#
PlatformerCharacter2D script

sing UnityEngine;
public class PlatformerCharacter2D : MonoBehaviour
{
	bool facingRight = true; // For determining which way the player is currently facing.
	[SerializeField] float maxSpeed = 10f; // The fastest the player can travel in the x axis.
	[SerializeField] float jumpForce = 400f; // Amount of force added when the player jumps. 
	[Range(0, 1)]
	[SerializeField] float crouchSpeed = .36f; // Amount of maxSpeed applied to crouching movement. 1 = 100%
	[SerializeField] bool airControl = true; // Whether or not a player can steer while jumping;
	[SerializeField] LayerMask whatIsGround; // A mask determining what is ground to the character
	Transform groundCheck; // A position marking where to check if the player is grounded.
	float groundedRadius = .2f; // Radius of the overlap circle to determine if grounded
	bool grounded = false; // Whether or not the player is grounded.
	Transform ceilingCheck; // A position marking where to check for ceilings
	float ceilingRadius = .01f; // Radius of the overlap circle to determine if the player can stand up
	Animator anim; // Reference to the player’s animator component.
	Transform playerGraphics; // Reference to the graphics so we can change directions
	void Awake()
	{
		// Setting up references.
		groundCheck = transform.Find("GroundCheck");
		ceilingCheck = transform.Find("CeilingCheck");
		anim = GetComponent<Animator>();
		playerGraphics = transform.FindChild ("Graphics");
		if (playerGraphics = null){
			Debug.LogError ("Well crap the game isnt working sorry we cant find grapfics object as a child of the player");
		}
	}
	void FixedUpdate()
	{
		// The player is grounded if a circlecast to the groundcheck position hits anything designated as ground
		grounded = Physics2D.OverlapCircle(groundCheck.position, groundedRadius, whatIsGround);
		anim.SetBool("Ground", grounded);
		// Set the vertical animation
		anim.SetFloat("vSpeed", rigidbody2D.velocity.y);
	}
	public void Move(float move, bool crouch, bool jump)
	{
		// If crouching, check to see if the character can stand up
		if(!crouch && anim.GetBool("Crouch"))
		{
			// If the character has a ceiling preventing them from standing up, keep them crouching
			if( Physics2D.OverlapCircle(ceilingCheck.position, ceilingRadius, whatIsGround))
				crouch = true;
		}
		// Set whether or not the character is crouching in the animator
		anim.SetBool("Crouch", crouch);
		//only control the player if grounded or airControl is turned on
		if(grounded || airControl)
		{
			// Reduce the speed if crouching by the crouchSpeed multiplier
			move = (crouch ? move * crouchSpeed : move);
			// The Speed animator parameter is set to the absolute value of the horizontal input.
			anim.SetFloat("Speed", Mathf.Abs(move));
			// Move the character
			rigidbody2D.velocity = new Vector2(move * maxSpeed, rigidbody2D.velocity.y);
			// If the input is moving the player right and the player is facing left…
			if(move > 0 && !facingRight)
				// … flip the player.
				Flip();
			// Otherwise if the input is moving the player left and the player is facing right…
			else if(move < 0 && facingRight)
				// … flip the player.
	line 60			Flip();
		}
		// If the player should jump…
		if (grounded && jump) {
			// Add a vertical force to the player.
			anim.SetBool("Ground", false);
			rigidbody2D.AddForce(new Vector2(0f, jumpForce));
		}
	}
	void Flip ()
		
	{
		
		// Switch the way the player is labelled as facing.
		
		facingRight = !facingRight;
		
		
		
		// Multiply the player’s x local scale by -1.
		
line 85	        Vector3 theScale = playerGraphics.localScale;
		
		theScale.x *= -1;
		
		playerGraphics.localScale = theScale;
		
	}
	
}

now the Platformer2DUserControl script

using UnityEngine;

[RequireComponent(typeof(PlatformerCharacter2D))]
public class Platformer2DUserControl : MonoBehaviour 
{
	private PlatformerCharacter2D character;
    private bool jump;


	void Awake()
	{
		character = GetComponent<PlatformerCharacter2D>();
	}

    void Update ()
    {
        // Read the jump input in Update so button presses aren't missed.
#if CROSS_PLATFORM_INPUT
        if (CrossPlatformInput.GetButtonDown("Jump")) jump = true;
#else
		if (Input.GetButtonDown("Jump")) jump = true;
#endif

    }

	void FixedUpdate()
	{
		// Read the inputs.
		bool crouch = Input.GetKey(KeyCode.LeftControl);
		#if CROSS_PLATFORM_INPUT
		float h = CrossPlatformInput.GetAxis("Horizontal");
		#else
		float h = Input.GetAxis("Horizontal");
		#endif

		// Pass all parameters to the character control script.
	line 37	character.Move( h, crouch , jump );

        // Reset the jump input once it has been used.
	    jump = false;
	}
}

I hope you can help me

Put it in orignal code