Brief Answer:
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Detailed Answer:
I read your question carefully and I understand your concern.

From your account it seems that the symptoms didn't include headache (if they did please tell me as it would raise the suspicion of cervical artery dissection) or other symptoms such as double vision, speech issues, weakness or numbness of the limbs etc which would raise the concern of stroke.

Otherwise this description of dizziness triggered by a sudden head movement would seem like an inner ear issue. The inner ear is one of the main organs involved in balance and movement of the crystals in its inner labyrinths may cause vertigo and dizziness often exacerbated or triggered by head movement. In order to alleviate the symptoms usually antihistamines like meclizine are used.

If any new symptoms appear or you have any other questions do not hesitate to write again.

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Brief Answer:
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Detailed Answer:
Sorry for taking a while to answer, your question has come right as I went to sleep.

There are no precise rules on how much to wait, I would wait 12 hours, but it depends on how much it bothers you as well, can be taken earlier.

It is an over the counter drug, prescription is not necessary. May cause some drowsiness so caution is needed if you need to drive.

Apart from medication if symptoms persist there is also a maneuver, a sequence of head movements called Epley maneuver which can be tried. It can lead to improvement in about half of the patients, should be performed by a physician though at least the first time.

Let me know if I can further assist you.

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Brief Answer:
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Detailed Answer:
I am glad you're feeling better.

If it was only the dizziness I would say the fact it improved after eating would indicate low sugar levels or low blood pressure.

However what doesn't fit with that is that it started so suddenly after that abrupt head movement, that is what made me suggest an inner ear issue. Blood sugar wouldn't change that quickly. Blood pressure may change when one changes position (called orthostatic hypotension), but it happens when one changes from supine to standing, while you were already standing. So hard to be sure.

Anyway if you are symptom free now it is hard to verify any of those hypothesis even if you were to be seen by your doctor as blood tests and pressure measurements should come out normal, so it will remain unresolved for the moment. If it repeats itself then should perhaps head to the ER to get a quick evaluation for blood pressure and some routine blood tests.

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