Brief Answer: So much disturbance has not been noted usually. Detailed Answer: Hello, Thanks for writing to us. Emergency contraception is very much effective when it is taken within the stipulated time interval. As it contains excess hormone, it tends to disturb the menstrual cycle as the hormonal balance is tampered with. The usual menstrual cycle may be delayed by about a week or two after inducing a withdrawal bleed a week after ingesting the pill; prolonged absence of a menstrual period calls for further investigation. In the current scenario, I would suggest a complete evaluation by a gynecologist along with a trans-vaginal sonogram. Since pregnancy has been excluded through a blood test, you may be going through a phase of hormonal imbalance and you would need a complete hormonal profile including the thyroid profile. Your symptoms point to hormone excess and stress could be adding to all. As far as my experience goes, Plan B does not cause so much of disturbance and you need to be investigated to manage further. Please maintain a healthy weight, some form of regular exercise and a healthy diet. You may need hormones for inducing withdrawal bleeding and later on for setting the cycle back on track. Hope your query has been answered. Please feel free to contact for further clarifications. I will be happy to help. regards, Shanti.V.

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