OK I had to look up how to tell the difference between a male and female hamster
Sexing Hamsters
To sex a hamster you need to be able to look at . This can be done in one of two ways:
Place the hamster on one hand, place your other hand over it's back and turn your hands over so that the hamster is lying on it's back.
Hold the hamster by the scruff of the neck in order to see underneath.
The concept of sexing any species of hamster is the same. The male is more elongated around the rear and more rounded than the female and this is particularly noticeable with Chinese Hamsters.