Same posts displaying in admin screen for all defined custom post types

I have created two custom post types, one called ‘my_product’ and one ‘my_homepage_item’. I created the first, made a number of product items, then created the homepage items category. Hitting “add item” successfully allows me to write a homepage item to the database, but when I view the custom post category in the admin menu, it is showing me the list of products. I cannot access the homepage item post types anywhere, as all admin pages other than the add-new page will only display content for the original products category. Has anybody else experienced this issue? I created a third post type, but it too only displays posts from the original product type.

Post type definition code:

function create_nti_product() {
	register_post_type( 'my_product',
		array(
			'labels' => array(
				'name' => __( 'Products' ),
				'singular_name' => __( 'Product' ),
				'add_new' => __( 'Add New' ),
				'add_new_item' => __( 'Add Product' ),
				'edit' => __( 'Edit' ),
				'edit_item' => __( 'Edit Product' ),
				'new_item' => __( 'New Product' ),
				'view' => __( 'View Product' ),
				'view_item' => __( 'View Product' ),
				'search_items' => __( 'Search Products' ),
				'not_found' => __( 'No products found' ),
				'not_found_in_trash' => __( 'No products found in Trash' ),
			),
			'public' => true,
			'show_ui' => true,
			'menu_position' => 21,
			'can_export' => true, /* Allow you to export the video items through the WP Export tool */
			'supports' => array( 'title', 'editor', 'custom-fields', 'thumbnail' ),
		)
	);
	register_post_type( 'my_homepage_item',
		array(
			'labels' => array(
				'name' => __( 'Homepage Items' ),
				'singular_name' => __( 'Homepage Item' ),
				'add_new' => __( 'Add New Homepage Item' ),
				'add_new_item' => __( 'Add Homepage Item' ),
				'edit' => __( 'Edit' ),
				'edit_item' => __( 'Edit Homepage Item' ),
				'new_item' => __( 'New Homepage Item' ),
				'view' => __( 'View Homepage Item' ),
				'view_item' => __( 'View Homepage Item' ),
				'search_items' => __( 'Search Homepage Items' ),
				'not_found' => __( 'No Homepage Items found' ),
				'not_found_in_trash' => __( 'No Homepage Items found in Trash' )
			),
			'public' => true,
			'show_ui' => true,
			'can_export' => true, /* Allow you to export the video items through the WP Export tool */
			'supports' => array( 'title', 'editor', 'custom-fields', 'thumbnail' ),
		)
	);
	// OK, what if we create a new one?
	register_post_type('whatiswrong',array('labels' => array('name' => 'Wrong!'),'public' => true));