I think you need to rule out anaemia and mentrual issues. Your age and problem doesn't require olanzapine.
Next Steps
check your haemoglobin levels, serum
calcium and
vitamin D, . take tablet albendazole 400mg one and next day start ferrous fumarate with ascorbic acid daily twice for 3months, that reduces fatigue due to anaemia.
Health Tips
tablet SHELCAL in afternoon , and keep monitoring the values( Haemoglobin and
calcium levels ).