php - Unexpected character in input: ''' (ASCII=39)

i have following code:

header( 'Content-type: text/xml' );

mysql_connect( 'domain', 'user', 'password' );
mysql_select_db( 'database' );

mysql_query("   INSERT INTO user(userName,password,email)
                VALUES(

                    '".$_POST['username']."',
                    '".md5($pass)."',
                    '".$_POST['email']."',          
 )" );

?>

When i try to load this in url:

http://xcode.domain.de/add.php?userName=test&password=test

I got this error on my server:

Warning: Unexpected character in input: ''' (ASCII=39) state=1 in /kunden//webseiten/xcode/add.php on line 15

Parse error: syntax error, unexpected '"' in /kunden/webseiten/xcode/add.php on line 15

can Somebody help on this?

thank you