So “every now and again” alludes to periodic rather than consistent. And at this point I only know 4 things about your practice - 30 minutes, no headstand/shoulderstand, lots of downward facing dog. It is thus quite challenging to weigh your practice (without knowing it).
Dehydration would be a state you would enter the practice with rather than one that would result in a 30 minute practice. If you are hydrated when you begin you’re likely not having a hydration issue.
Inversions, for some, can cause dizziness when exiting the pose however the blood pressure re-stabilizes in a fairly short period of time and it would be unusual for that to continue after the practice.
There are several other possibilities. It is possible the sequence you are doing does aggravates vatta, one of the three ayurvedic constitutions. Light-headed, dizzy, floating, scattered would be potential indicators of aggravated vatta. In those cases the sequence (and diet) could be altered to balance the vatta with it’s two siblings.
It is also possible you are not taking a Savasana in closing your practice. It is so very important to allow the body to shift following the doing of asana. It’s a pose that integrates that which comes before it into the nervous system. In my experience nausea is more common than dizziness HOWEVER every human being is unique and responds to this or that differently.
Finally it could be a lack of depth in breath or an overdoing which results in choppy breath.
Hope this is helpful.
gordon
