ok, are you 5 weeks into flowering???? if so, you should definately know if its male or female by now.. but!!
Im guessing you are just 5 weeks into growing.... have you switched to 12/12 yet??? if not then there wont be a way of telling..
you can only tell if you are in the flowering cycle (12/12)
easy way to tell: Balls are for BOYS pistils (punani) are for girls... not hard