Question: should I separate the males from the females?
Answer : Yes, you should, because females become sexually mature at 4-5 weeks while males at 3-4 weeks. If the female become pregnant at such little age it can be a danger to her life. You should also keep in mind that males should be kept in small groups of 1-2 because they can fight with each other to gain higher rank in the group.
If you don’t know how to tell males from females I will tell you. While both have “Y” shaped configuration of the genitalia, you can spot a small dot in the center of “Y” in males. You can softly press around this dot to see the male organ come out.