diff --git a/src/wp-includes/shortcodes.php b/src/wp-includes/shortcodes.php
index 057fad73be..2d15fb584c 100644
--- a/src/wp-includes/shortcodes.php
+++ b/src/wp-includes/shortcodes.php
@@ -90,13 +90,13 @@ function add_shortcode($tag, $func) {
 	global $shortcode_tags;
 
 	if ( '' == trim( $tag ) ) {
-		$message = __( 'Invalid shortcode name.  Empty name given.' );
+		$message = __( 'Invalid shortcode name: Empty name given.' );
 		_doing_it_wrong( __FUNCTION__, $message, '4.4.0' );
 		return;
 	}
 
 	if ( 0 !== preg_match( '@[<>&/\[\]\x00-\x20]@', $tag ) ) {
-		$message = sprintf( __( 'Invalid shortcode name: %s  Do not use spaces or reserved chars: & / < > [ ]' ), $tag );
+		$message = sprintf( __( 'Invalid shortcode name: %s. Do not use spaces or reserved characters: & / < > [ ]' ), $tag );
 		_doing_it_wrong( __FUNCTION__, $message, '4.4.0' );
 		return;
 	}