Brief Answer:
Hormonal disturbance or stress

Detailed Answer:
Hi dear, I have gone through your question and understand your concerns. Delayed periods can be due to pregnancy or any hormonal disturbances like hypothyroidism, hyperprolactemia or polycystic ovarian disease. It can also be delayed due to stress.
Since you are not sexually active, pregnancy is ruled out.
I will suggest you to get your hormonal profile done including thyroid hormone levels, prolactin levels and an ultrasound done. This will confirm your diagnosis so that further management can be done.
Hope you found the answer helpful. Please do get back for further queries.
Wishing you good health.
Regards,
Dr Deepti Verma

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