Brief Answer:
Usually a benign condition

Detailed Answer:
Hi XXXXXXX and XXXXXXX

Thanks for your query and an elucidate history.

Since you are young, just 26 years of age, cancers (the most dreaded / feared = phobia) are not common to occur so early.

Most of the times the reason can be just physiological as one of the reasons is secretion by the ducts in response to the suckling / fondling / stimulation in any form. And you have the history.

Another non-cancerous reasons are:
Fibrocystic disease and many more benign conditions that the breast can have at your age due to strong hormonal changes and responses.

Cancer is a rare cause and usually the discharge is reddish and the nipples and / or areola do show the changes, the painless lump may be palpable
By this time due to the practice of your husband the lump should have been detected by both of you.

Since you have given a history of a ''drop'' of white fluid coming out of left nipple, that too few days back, and not again, ideally there is no reason to be serious about it.

But since the cancer is a dreaded disease and to clear the doubts from the minds of both of you I would suggest you the following simple things::
-Self examination by you and your Husband, This is done by the flat of the palm and by the non-painful pinching palpation of both the breasts. Also palpate the axillae (armpits) and neck for any possible swelling. You both can do this easily...
-Get examination done by a General Surgeon or a Surgical Oncologist.
-Mammography and / high resolution ultrasonography / (MRI of the breasts if your city of residence has the facility).

All these things are basically done if calm the mind by ''ruling out'' any deep seated problem.

May I please know ::
Years of marriage.
Any child; if yes - breast feeding.
Any other medical problem you have

I think nothing much to worry as this is common to have a few drops of white discharge in females of your age.
All the exercises are a must to keep the doubts off the mind so that we do not miss anything and the future life becomes without and stress and anxiety- which is more bothersome than the discharge you had.

I hope you both agree with me, I have tried my best to give a chronological activity to have your doubts cleared to have the best possible life on the eve of a happy new years ( Wishing you both a very happy and healthy new year 2015).
Please feel free to ask for more if you feel that there is a gap-of-communication.

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Brief Answer:
PCOS gives hormonal imbalance, migraine not related

Detailed Answer:
Hi.
Thank you for your feedback.

The history of early PCOS, medication and delayed periods do suggest hormonal imbalance and can be of the reasons for your present finding.

I think migraine is not related to this problem.
Get the review for PCOS- ultrasonography, hormonal studies done under the guidance of the Gynecologist and get treated well.

Was there any recurrence of the discharge from the nipple?
Planning / wanting to have a baby?

Rest of the discussions remains as mentioned.

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