Get attachments only for this post

by

Try this using the get_children function:

global $post;
$args = array(
    'numberposts' => -1,
    'order'=> 'ASC',
    'post_mime_type' => 'image',
    'post_parent' => $post->ID,
    'post_status' => 'any',
    'post_type' => 'attachment'
);
$attachments = get_children($args);

Reference: http://codex.wordpress.org/Function_Reference/get_children