Using get_post_meta with new_to_publish

I’m trying to read the custom fields set by the user when publishing a new post:

function doSomething($post) {

   $meta = get_post_meta($post->ID);

   error_log("post meta: ".print_r($meta, true));

}

add_action("new_to_publish", "doSomething", 999);
add_action("draft_to_publish", "doSomething", 999);
add_action("pending_to_publish", "doSomething", 999);

The custom fields are there for draft_to_publish but not for new_to_publish.

If I use save_post it seems to work every time, but I need it to only run when the status is set to publish for the first time…