Brief Answer:
This could be due to stress and anxiety

Detailed Answer:
Hello ma'am
I share your concern
You need not to worry I will try to help you out in best possible way
At your age it may happen that duration of sleep as well as sleeping habits changes
This could be due to stress and anxiety, Low energy or nutritional deficiency like anaemia
So you need not to be panic.
I would like further information to guide you better
Your complete medical history like your weight height, history of diabetes or any other disease
Are you having day time sleepiness

Please follow these guidelines
This can be caused by stress and anxiety So just relax and enjoy your life
Exercise regularly 30 to 45 minutes walking , jogging or swimming
Have lots of fresh fruits and vegetables
You should do Yoga and mediation, deep breathing and relaxation exercises will definitely help you as well.

Hope this helps you
thanks for your question, follow up questions are most welcome
Wishing you good health and vitality

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