check online for photos of the tails...males and females can be visually sexed. If they had an underweight snake, they were probably not too keen on the truth of it was a male or female. Also they may not have the age right...but i think females do get bigger than that length. ALso, as long as the snake is well fed, and not freaking out or trying to get out or acting weird in any other way...it may just not be hungry...which is a compliment! But i would totally worry and be on here too, so it's easy for me to say hehe