How to Make Pressing a Button Not Trigger Other Events?

In my game I have a ball spawner that spawns a ball every time I tap the screen. I also have a pause button. When I tap the paused button, the spawner still spawns the ball even though I have told it not to using code. Here is my code:

Spawner:
public GameObject Ball;
// Use this for initialization
void Start () {

}

// Update is called once per frame
void Update () {
	if (Input.GetMouseButtonDown (0)) {
		Instantiate (Ball, transform.position, Quaternion.identity);
	}
}

}

Pause Buttons:
public class PauseControllerScript : MonoBehaviour {

public string mainMenu;

public bool isPaused;

public GameObject pauseMenuCanvas;

public GameObject spawner;

public GameObject cups;

// Use this for initialization
void Start () {
	
}

// Update is called once per frame
void Update () {
	if (isPaused) {
		pauseMenuCanvas.SetActive (true);
		Time.timeScale = 0f;
		spawner.GetComponent <BallSpawn> ().enabled = false;
	} else {
		pauseMenuCanvas.SetActive  (false);
		Time.timeScale = 1f;

	}
		

}

public void Resume () {

	isPaused = false;

}

public void Quit () {
	SceneManager.LoadScene ("StartScreen");

}

public void Paused () {
	isPaused = !isPaused;
}

public void Yes () {
	isPaused = true;
}

}

void Update ()
{
if (Input.GetMouseButtonDown (0) && !isPaused)
{
Instantiate (Ball, transform.position, Quaternion.identity);
}
}

and why r u using your pause code in Update() use On button click
and if you want to avoid the click on pause bt dont use getmousebuttondown use ui image filled with screen size