trouble with db and playerPrefs

here is my script:

 private var secretKey="RomanIsGod"; // Edit this value and make sure it's the same as the one stored on the server
 var highscoreUrl="http://www.mysite.com/folder/game/file.php?";    
 
 var curExp : float;
 var maxExp : float;
 var level : float = 1;
 var expTexture : Texture;
 var w : float = 900;
 var style : GUIStyle;
 
 function Start() {
     SetPlayerName = PlayerPrefs.GetString("playerName");
     //style.normal.textColor = Color.yellow;
     //style.fontSize = 10;
     getScores(SetPlayerName);
     
 }
 
 function Update() {
     SetPlayerName = PlayerPrefs.GetString("playerName");
     getScores(SetPlayerName);
 }
 
 // Get the scores from the MySQL DB to display in a GUIText.
 function getScores(SetPlayerName) {
     var highscore_url;
     //var highscore_url = highscoreUrl + "name=" + SetPlayerName + "";
     Debug.Log (highscore_url);
     gameObject.guiText.text = "";
     hs_get = WWW(highscoreUrl);
     yield hs_get;
  
     if(hs_get.error) {
         print("There was an error getting the high score: " + hs_get.error);
     } else {
         gameObject.guiText.text = hs_get.text; // this is a GUIText that will display the scores in game.
         Debug.Log (hs_get.text);
         var getXP : int = hs_get.text.string;
         curExp = getXP;
     }
 }
 
 function OnGUI () {
         
     GUI.depth = 200;
     Debug.Log ("scores: " + getScores);
     GUI.DrawTexture(Rect(Screen.width / 2 - 450, Screen.height - 48, w *(curExp/maxExp), 30), expTexture);
 }
 
 function waitTen()
 {
     yield WaitForSeconds(10);
 }

the problem is here:

 var highscore_url;
 //var highscore_url = highscoreUrl + "name=" + SetPlayerName + "";

which is supposed to do:

 GUI.DrawTexture(Rect(Screen.width / 2 - 450, Screen.height - 48, w *(curExp/maxExp), 30), expTexture);

this is the line bar that shows your current level progress in xp.

when I change the the "highscore_url" to the one that sets the "SetPlayerName" line the whole thing breaks, and I am pretty good with php.. that part of the code and the database are fine and I get the return variables that I am looking for.

I am trying to set the curExp and the maxExp which come from the database as curExp/score and maxExp/level.

what am I doing wrong?