GUI not working correctly? (Double tooltip display)(c#)

Okay, I HATE GUI coding. It makes VERY little sense to me, so PLEASE tell me what I"m doing wrong :(

If you hover over the first item in the array with 2 items in it (haven't tried with more) it gives you double the tooltip, but the second item in the array works properly.

     void OnGUI()
     {
         
         if(inventoryOpen)
         {
         int invcount = 0;
         GUI.BeginGroup (new Rect(Screen.width/2 +100, Screen.height - 200, 400, 100));
         GUI.Box (new Rect(0,0,400,100), "Weapons");
         foreach(GameObject inv in inventory)
             {
             if(invcount < inventory.Count)
                 {
                     invcount ++;
                 }
             if(GUI.Button (new Rect(10 + (invcount - 1) * 65,20,60,60),new GUIContent(inv.name, "Damage: " + inventory[invcount-1].GetComponent<Item>().dmg)))
                 {
                     Debug.Log ("equipping" + inv.name);
                     //Write this later
                 }
             GUI.Label (new Rect(10 + (invcount - 1) * 65, 70, 100, 30), GUI.tooltip);
             }
         
         GUI.EndGroup();
         }
     }