You can try to add
'meta_key' => '_thumbnail_id',
to your input arguments:
$args = array( 'numberposts' => 5,
'orderby' => 'date',
'order' => 'DESC',
'post_type' => 'post',
'post_status' => 'publish',
'meta_key' => '_thumbnail_id',
);
to query only posts with thumbnails (i.e. featured images).
ps: instead of this structure:
if ( !has_post_thumbnail() ) {
continue;
} else {
}
you can in general use
if ( has_post_thumbnail() ) {
}
But you can now skip the if
-sentence part in the loop since you are now only fetching posts with featured images.