Need help making a touch screen button.

I left notes in the code about what the problem is, but in short, I need to make it so you can't touch the screen thirty times in three seconds while only playing a sound clip once.

 using UnityEngine;
 using System.Collections;
 
 //Using C# for those who are wondering.
 //Should I use Java? Is it easier?
 
 public class Button : MonoBehaviour {
 
     public AudioClip team;
     public AudioSource source;
     public float volLowRange = 1.0f;
     public float volHighRange =1.0f;
 
     void Start () {
         source = GetComponent<AudioSource> ();
         //Getting the audio clip for later, I think...
     }
 
     void Update () {
         if (Input.GetButtonDown ("mouse 1")) { //Clicky clicky (or tappy tappy on the touch screen)
             //I put Mouse 0 in the input but named it mouse 1, personal preferences
 
             source.PlayOneShot (team,1f); //Play the sound
 
             //I need something here I think to make it pause about 3 seconds
             //I tried yield, it doesn't work for some reason...
             //I also need to change the button sprite before the pause and change it back,
             //make things a bit more real. I got the sprite ready, just need to know what I'm doing.
         
         }
         if (Input.GetButtonDown ("back")) { //Backspace
             Application.Quit (); //Shutdown
         }
     }
 }
 //For anyone curious as to what I'm doing, I'm making a button that plays a sound clip of Jack Black saying
 //"That's f***ing Team Work" as you tap the touch screen of an Android or Windows 8.1 device. That's it...
 //Only problem, the development build I have right now lets you spam click it, and even though I love spamming
 //I still need it limitted for when I upload it to the app store.
 //If someone also knows how to make it so only touching the button sprite makes it play instead of anywhere on the
 //screen, I'd really appreciate it.
 //Definitely giving credit to anyone who can even help a bit.
 //And for those asking why... It was originally an inside joke at 2 AM, but it could be fun. Better than Montage Parodies.