How to restrict a button for a second

I know I kind of asked this question one time, but no-one answered me correctly. Firstly Heres my script

var targetScript : ChangeSprite;
    var AcceptInput : boolean = true;
    private static var score : int = 0;
    var guiScore : GUIText;


function Start ()
{
guiScore.text = "Score: 0";
}


function OnMouseDown () {
if(!AcceptInput)
{
return;
}
AcceptInput = false;


targetScript = GameObject.Find("Shape").GetComponent(ChangeSprite);


GameObject.Find("Shape").GetComponent(ChangeSprite).enabled = true;
Debug.Log("Clicked");

if(targetScript.spriteRenderer.sprite == targetScript.diamond) {
AcceptInput = true;
score += 1;
guiScore.text = "Score: " + score;
}


else{
Debug.Log("Wrong Answer!");
}

}

function OnMouseUp () {
AcceptInput = true;
GameObject.Find("Shape").GetComponent(ChangeSprite).enabled = false;
}

and the script that is being enabled :

var diamond : Sprite;
var circle : Sprite;
var triangle : Sprite;
var square : Sprite;
var number : int;
var spriteRenderer : SpriteRenderer;

function OnEnable() {

spriteRenderer = gameObject.GetComponent(SpriteRenderer);

number = Random.Range(1,5);

if(number == 1) {
spriteRenderer.sprite = diamond;
}

else if(number == 2) {
spriteRenderer.sprite = circle;
}

else if (number == 3) {
spriteRenderer.sprite = triangle;
}

else {
spriteRenderer.sprite = square;
}


}

function OnEnable() {

spriteRenderer = gameObject.GetComponent(SpriteRenderer);

number = Random.Range(1,5);

if(number == 1) {
spriteRenderer.sprite = diamond;
}

else if(number == 2) {
spriteRenderer.sprite = circle;
}

else if (number == 3) {
spriteRenderer.sprite = triangle;
}

else {
spriteRenderer.sprite = square;
}


}

What the script does is OnMouseDown, it enables a disabled script which changes an object’s sprite. And if the sprite is the correct answer, it would add a score. If not, Debug.Log(“wrong Answer!”) I used the accept input thing because if I don’t it would play through the sprites non stop because the script wouldn’t be disabled. But the thing is, if I press the button, it would add the score before the sprite would even be displayed on the screen, so I want to make a restriction so that you can only press the button and the button can only work when the actual sprite is displayed. Does anyone have any Real
ideas? Thank You

Change OnEnable function to Start.