Trouble With Disableing a Function

Okay so I have been working on an FPS, (like most people) and i need to disable my Reload function while I'm shooting my gun. I can get it to work by putting if(!Firing){return} at the beginning of the function and it won't reload at all. Even when I'm all out of ammo. Any help would be appreciated.

 var fireRate : float = .5;
 
 var bulletShell : Transform;
 
 var BulletShellSpead : float;
 
 var MuzzleFlash : Transform;
 
 var Smoke : Transform;
 
 var Sound : AudioClip;
 
 var strayFactor : float;
 
 var bulletPrefab : Transform;
 var bulletSpeed : int;
 
 var GrenadeSpeed : float;
 var Grenade : Transform;
 var GrenadeAmmo : int;
 
 var MaxAmmo : int;
 var CurrentClip : int = 10;
 var CurrentExtraAmmo : int = 100;
 var ClipSize : int = 10;
 
 var ReloadTime : float;
 var ClickSound : AudioClip;
 var ReloadSound : AudioClip;
 var Reloading : boolean = false;
 
 var Firing : boolean = false;
 
 private var nextFire = .5;
 
 function LateUpdate()
 {
     if(GrenadeAmmo < 0)
         GrenadeAmmo = 0;
         
     if(CurrentClip < 0)
     CurrentClip = 0;
     
     if(CurrentClip > MaxAmmo)
         CurrentClip = MaxAmmo;    
         
     if(Input.GetButtonDown("Fire1")&& CurrentClip <= 0)
         {
             NoAmmo();
         }
 }
 
 function Update() 
 {
         if(Input.GetKeyDown(KeyCode.R))
         {
             Reload();
         }
         
         if(Input.GetKeyDown(KeyCode.E))
             {
                 GrenadeThrow();
             }
         if(CurrentClip > 0)
         {
             if(Input.GetButtonDown("Fire1") && Time.time > nextFire)
             {
             nextFire = Time.time + fireRate;
             
             Firing = true;
             print("ouch");
             
             Shoot();
         
             var bulletShell = Instantiate(bulletShell, GameObject.Find("Spawn3").transform.position, Quaternion.identity);
             bulletShell.rigidbody.AddForce(transform.right * BulletShellSpead);
         
             var MuzzleFlash = Instantiate(MuzzleFlash, GameObject.Find("Spawn").transform.position, Quaternion.identity);
         
             var Smoke = Instantiate(Smoke, GameObject.Find("Spawn").transform.position, Quaternion.identity);
     
             animation.Play("PistolShoot");    
             audio.PlayOneShot(Sound);
             
             Firing = false;
             }    
         }
 }
 
 function GrenadeThrow()
 {
     if(GrenadeAmmo > 0)
         {
             var grenade = Instantiate(Grenade, transform.position, Quaternion.identity);
             grenade.rigidbody.AddForce(transform.forward * GrenadeSpeed);
         }
             GrenadeAmmo --;
 }
 
 function Shoot()
 {
     var randomNumberX = Random.Range(-strayFactor, strayFactor);
     var randomNumberY = Random.Range(-strayFactor, strayFactor);
     var randomNumberZ = Random.Range(-strayFactor, strayFactor);
         
     var bullet = Instantiate(bulletPrefab, GameObject.Find("Spawn").transform.position, transform.rotation);
     
     bullet.transform.Rotate(randomNumberX, randomNumberY, randomNumberZ);
     bullet.rigidbody.AddForce(bullet.transform.forward * bulletSpeed);
             
     bullet.tag = "Bullet";
     CurrentClip --;
 }
 
 function Reload()
 {    
     if(!Firing)
     {
     return;
     }
 
     if(CurrentExtraAmmo <= 0)
     {
         NoAmmo();
     }
     else
     {
     if(CurrentClip <= 14)
     {
     Reloading = true;
     
     animation.Play("Reload");
     audio.PlayOneShot(ReloadSound);
     }
     yield WaitForSeconds(ReloadTime);
 
     Reloading = false;
 
     if(CurrentExtraAmmo >= ClipSize - CurrentClip)
     {
         CurrentExtraAmmo -= ClipSize - CurrentClip;
         CurrentClip = ClipSize;
     }
     
     if(CurrentExtraAmmo <= ClipSize - CurrentClip)
     {
         CurrentClip += CurrentExtraAmmo;
         CurrentExtraAmmo = 0;
         }
     
     }
     
     
 }
 function NoAmmo()
 {
     Firing = false;
     animation.Play("Emepty");
     audio.PlayOneShot(ClickSound);
 }
 
 function OnGUI()
 {
     if(CurrentClip <= 5)
     {
     GUI.contentColor = Color.red;
     }
 
     GUI.Box(Rect(Screen.width / 1.16, Screen.height / 80, 100, 20), ""+ CurrentClip + "/" + CurrentExtraAmmo);
 }