Photon Errors?

This is a collection of many errors I get when I try to run the game with Photon Network.

I'm using Photon, and when i run the game, the console gives me an error: NullReferenceException: Object reference not set to an instance of an object Raycast.Update() (at Assets/Scripts/Raycast.cs:43)

The error is in the line if (pv.isMine == true)

I'm trying to check if the character is mine, so I can control it. Here is my void update for Raycast.cs:

 void Update () 
     {
         PhotonView pv = PhotonView.Get(this);
     
     if (pv.isMine == true)
     {
         PlayerStatecontroller();
         PlayerAnims();
         
         ammocount.text = ammo.ToString();
         
         var ray = new Ray(Camera.main.transform.position, Camera.main.transform.forward);
         RaycastHit hit;
         if (cooldownRemaining >= 0)
         {
             cooldownRemaining -= Time.deltaTime;
         }
         else if (cooldownRemaining < 0)
         {
             cooldownRemaining = 0;
         }
         if(Input.GetMouseButton (0) && cooldownRemaining <= 0 && ammo >= 1)
         {
             weapon.animation.Play("recoil");
             ammo -= 1;
             audio.PlayOneShot (shot, 0.5f);
             
             if(Physics.Raycast(ray, out hit, 300))
             {                
                 Instantiate(sparks, hit.point, Quaternion.identity);
                 
                 if (hit.collider.gameObject.tag == "Enemy" || hit.collider.gameObject.tag == "Player")
                 {
                     hit.collider.SendMessageUpwards("takeCurDmg", dmgStat, SendMessageOptions.DontRequireReceiver);
                     hit.collider.SendMessageUpwards("takeArmDmg", aPierce, SendMessageOptions.DontRequireReceiver);
                     Debug.DrawLine(ray.origin, hit.point, Color.red);
                     //Debug.Log (hit.collider.tag);
                     //Debug.Log ("Hit an enemy");
                 }
             }
             
             //flare.emit = false;
             
             cooldownRemaining = cooldown;
         }
         
         if (Input.GetKeyDown (KeyCode.R) == true)
         {
             ammo += 150;
         }
     }
 }

(Sorry if its long)

Another problem I get is that I define a GUIText, but when I run the game, the GUIText appears, but it doesn't update. A minor problem compared to the first one. Thanks in advance for help.