When my button is pressed the action reapeats

I'm making a gun customization scene for my game and i'm making is so that when you press a button some more buttons show up but when i try to click one of my buttons (They are planes not Gui) it starts repeating either the "BackButton" or the "MainButotn4". When I click on a button while "MainButton4" is repeating "MainButton2" flashes then 4 keeps repeating. Anyone know how I can make it so that when one button is pressed it stays pressed and doesn't repeat. Here are me scripts:

Game Logic:

 var MainSightID : int = 0;
 var MainMuzzleID : int = 0;
 var MainGuns : int = 0;
 var MainSubButtons : int = 0;
 
 function Update () {
 
 }

Button Logic:

 var SubButtons : int = 0;
     var AssultRifleACWR : GameObject;
     var PistolM9 : GameObject;
     var ShotgunMCS : GameObject;
     var SniperBarret : GameObject;
 
 var GameLogicObj : GameObject;
 
 function Awake(){
     GameLogicObj = GameObject.FindGameObjectWithTag("Game_Logic");
 }
 
 function Update () {
     Debug.Log (SubButtons);
 
     SubButtons = GameLogicObj.GetComponent("Game_Logic").MainSubButtons;
 
     if (SubButtons == 0){
         AssultRifleACWR.SetActive(false);
         PistolM9.SetActive(false);
         ShotgunMCS.SetActive(false);
         SniperBarret.SetActive(false);
     }
     if (SubButtons == 1){
         AssultRifleACWR.SetActive(true);
         PistolM9.SetActive(false);
         ShotgunMCS.SetActive(false);
         SniperBarret.SetActive(false);
     }
     if (SubButtons == 2){
         AssultRifleACWR.SetActive(false);
         PistolM9.SetActive(true);
         ShotgunMCS.SetActive(false);
         SniperBarret.SetActive(false);
     }
     if (SubButtons == 3){
         AssultRifleACWR.SetActive(false);
         PistolM9.SetActive(false);
         ShotgunMCS.SetActive(true);
         SniperBarret.SetActive(false);
     }
     if (SubButtons == 4){
         AssultRifleACWR.SetActive(false);
         PistolM9.SetActive(false);
         ShotgunMCS.SetActive(false);
         SniperBarret.SetActive(true);
     }
 
 }

Button Script:

 var GameLogicObj : GameObject;
 var ButtonID : String = "";
 
 function Awake(){
     GameLogicObj = GameObject.FindGameObjectWithTag("Game_Logic");
 }
 
 function OnMouseEnter (){
 renderer.material.color = Color.gray;
 }
 function OnMouseExit (){
 renderer.material.color = Color.white;
 }
 
 function Update (){
     if(Input.GetMouseButtonDown(0)){
         if(ButtonID == "BackButton"){
             GameLogicObj.GetComponent("Game_Logic").MainSubButtons = 0;
         }
     }
     if(Input.GetMouseButtonDown(0)){
         if(ButtonID == "MainButton1"){
             GameLogicObj.GetComponent("Game_Logic").MainSubButtons = 1;
         }
     }
     if(Input.GetMouseButtonDown(0)){
         if(ButtonID == "MainButton2"){
             GameLogicObj.GetComponent("Game_Logic").MainSubButtons = 2;
         }
     }
     if(Input.GetMouseButtonDown(0)){
         if(ButtonID == "MainButton3"){
             GameLogicObj.GetComponent("Game_Logic").MainSubButtons = 3;
         }
     }
     if(Input.GetMouseButtonDown(0)){
         if(ButtonID == "MainButton4"){
             GameLogicObj.GetComponent("Game_Logic").MainSubButtons = 4;
         }
     }
 }