Dont worry about it, mine has had clear tubs for water since it was small, caught pooping plenty of times, never showed signs of anything until he was about a year old. The other little one I have is 11 months old has yet to show me anything as of yet but its looking male. give it time shell show you when shes ready.
We just fed him and watched as he went into his water to "go", hemipenes ahoy! Now I need a girl
How big are they? Watch them when they go to the bathroom (usually right after a meal) see if they evert hemipenes. Otherwise you will have to wait until they get bigger...