OnMouseDown Firing When I Miss 2DCollider

So, today when I woke up I was playing around with my game and for some reason when I was not clicking the 2DCollider the OnMouseDown() event was firing regardless of where I clicked. So I tried to troubleshoot the problem, but I have had no success. The weird thing is that the first click only triggers the OnMouseDown() event when I hit the 2DCollider, but all events thereafter are triggered when I click anywhere.

The game object has no GUIElement on it and uses a PolygonCollider2D on it. I have paused the game after to see if the collider or anything else on the gameobject changes, but nothing happens. I am using C# for all my scripting.

Thank you for your help.

Here is my code

 usingUnityEngine;
 usingSystem.Collections;
 
 publicclassGoat : MonoBehaviour {
 privatestaticSprite[] goats;
 privatestaticstring[] goatNames;
 
 voidAwake(){
 Application.targetFrameRate = 60;
 }
 
 voidOnMouseDown () {
 ScoreTracker.incrementScore ();
 increaseGoatSize ();
 audio.Play();
 }
 
 voidOnMouseUp () {
 resetGoatSize ();
 }
 
 //LoadsallGoatssoIcanchangetheGoatifIeverneedto.
 voidStart () {
 goats = Resources.LoadAll<Sprite> ("Sprites/Goats");
 goatNames = newstring[goats.Length];
 
 for(inti=0; i< goatNames.Length; i++) {
 goatNames[i] = goats[i].name;
 }
 }
 
 voidUpdate () {
 
 }
 
 //ChangestheGoat
 privatevoidswitchGoat (stringgoatName) {
 SpriteRendererrenderer = GetComponent<SpriteRenderer>();
 renderer.sprite = goats[System.Array.IndexOf(goatNames, goatName)];
 transform.position = newVector3 (0.18f, 0.5f, 0);
 addCollider ();
 }
 
 privatevoidincreaseGoatSize () {
 transform.localScale = newVector3(1.25f, 1.25f);
 }
 
 privatevoidresetGoatSize () {
 transform.localScale = newVector3(1f, 1f);
 }
 
 //WhenIchangetheGoatIhavetochangethecollideraseachGoatisalittledifferent
 privatevoidaddCollider () {
 Destroy (renderer.collider2D);
 PolygonCollider2Dcollider = (PolygonCollider2D) gameObject.AddComponent<PolygonCollider2D>();
 collider.enabled = true;
 }
 }