SceneKit - UILabel Not Updating - Swift - ios

Question

My UILabel in my SceneKit project will NOT update, and any help would be greatly appreciated! First I create the label
class GameViewController: UIViewController, SCNSceneRendererDelegate, UIGestureRecognizerDelegate, SCNPhysicsContactDelegate {
...
var highscore = Int()
var score = Int()
var scoreLabel = UILabel()
var highScoreLabel = UILabel()
...
Then I move into a function that creates the scene, which is called in the ViewDidLoad, and also in a function which is called later on when my character "dies."
func createScene(){
score = 0
...
scoreLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.view.frame.width, height: 100))
scoreLabel.textAlignment = .Center
scoreLabel.center = CGPoint(x: self.view.frame.width / 2, y: self.view.frame.height / 2 - self.view.frame.height)
scoreLabel.textColor = UIColor.grayColor()
self.view.addSubview(scoreLabel)
highScoreLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.view.frame.width, height: 100))
highScoreLabel.textAlignment = .Center
highScoreLabel.center = CGPoint(x: self.view.frame.width / 2, y: self.view.frame.height / 2 + self.view.frame.height)
highScoreLabel.textColor = UIColor.grayColor()
highScoreLabel.text = "Highscore : \(highscore)"
self.view.addSubview(highScoreLabel)
scoreLabel.alpha = 0
highScoreLabel.alpha = 0
UIView.animateWithDuration(0.5, delay: 1, usingSpringWithDamping: 0.4, initialSpringVelocity: 0.5, options: UIViewAnimationOptions.CurveLinear, animations: ({
() in
self.scoreLabel.alpha = 1
self.highScoreLabel.alpha = 1
self.highScoreLabel.center = CGPoint(x: self.view.frame.width / 2, y: self.view.frame.height / 2 + self.view.frame.height / 2.5)
self.scoreLabel.center = CGPoint(x: self.view.frame.width / 2, y: self.view.frame.height / 2 - self.view.frame.height / 2.5)
}), completion: nil)
This loads the scoreLabel and highScoreLabel onto the scene with an animation.
In the game, I have it so 2 SCNNodes collide, and this would call the addScore function...
func AddScore(){
score++
dispatch_async(dispatch_get_main_queue(), {
self.scoreLabel.text = "Score : \(self.score)"
})
print(score)
if score >= highscore{
highscore = score
let userDefault = NSUserDefaults.standardUserDefaults()
userDefault.setInteger(highscore, forKey: "highscore")
}
}
This function adds 1 to the score, and because I have the print statement, I can see that the score is going up, but my label will NOT update. I've put it into a dispatch_async like this...
override func viewDidLoad() {
super.viewDidLoad()
scene.physicsWorld.contactDelegate = self
self.createScene()
}
and that doesn't do anything. So, if I haven't made it clear, what am I doing wrong that my scoreLabel is not updating? Any help would be greatly appreciated! :)