Brief Answer:
Details below.

Detailed Answer:
Hello,
Thanks for trusting us with your health concern.
I think you are easing off into the peri menopause, where cycles would get irregular / delayed and then stop gradually.
Other than peri menopause - stress, tensions on personal or professional front, unaccustomed exercise, rapid changes in your weight, ingestion of hormonal medications, late nights, erratic eating, changes in climate or altitude, travelling - all these can interfere with your cycles.
You also need to rule out pregnancy by doing a pregnancy test available over the counter.
It would be good to get your TSH ( thyroid hormone level ) checked, as thyroid disturbances can delay periods
Also, while the blood work is being done, get your FSH, LH and serum estradiol levels checked - they would tell you if menopause is near.

Please feel free to discuss further. I will be glad to answer the follow up queries that you have.
Wishing you good health.
Regards.
Dr. Rakhi Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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Brief Answer:
Nothing bad.

Detailed Answer:
Hello.
Thanks for writing again.
If there is no sudden acute pain then any serious problem is not likely. You can wait for few days for your periods to start spontaneously.
Hope my answer is helpful.
Do accept my answer in case there are no further queries.
Regards.

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