Welcome cyrce to the forums.
What the (3) means normally is that the shortcut is the 3rd iteration of a shortcut to itunes.
some could be shortcuts to the older version of itunes.
Best way is to delete all the itunes shortcuts and make a new one to the itunes executable.
you can right click on the start menu item for itunes and selecting
pin to taskbar and you should have the correct one on your taskbar.