Movement with Timer

#pragma strict
    var count : int;
    var countText : GUIText;
    var winText : GUIText;
    var jumpheight : float;
    var myTimer : float = 5.0;
    var display : GUIText;



function Start()
{
    count = 0;
    countText.text = "Counter: " + count.ToString();
    winText.text = " ";
}

function FixedUpdate () {
    var horizontal : float = Input.GetAxis("Horizontal");
    var vertical : float = Input.GetAxis("Vertical");

    var speed : float = 3;


    rigidbody.AddForce(Vector3(horizontal*speed,0,vertical*speed));

    if (Input.GetButton("Jump")) {
        Jump();
    }
    if(myTimer > 0){
        myTimer -= Time.deltaTime;
        var postedTime = Mathf.Floor(myTimer);
         display.text = "Time Remaining: " + postedTime;
    }
    if(myTimer <= 0){
        //do something!
    }

 }

// Destroy everything that enters the trigger


function Jump() {

        rigidbody.AddForce(Vector3.up * jumpheight);

    }