So I know that when you stand up quickly gravity pulls blood from your brain towards your feet and blood doesn't return to the brain until the next heart beat. With a slow pulse, this takes a second or two and that is enough time to feel the lack of oxygen in the symptom of lightheadedness or dizziness. Bur I've been smoking in my closet with a gravity bong and I would take the hit on the ground, then stand on a step-stool and blow the smoke in the attic. Every time I would get severe dizziness (which I understand) but I would almost have a seizure. Is this just from quickly getting up or does taking a hit from my gravity bong make it a lot worse? (Sorry for the run on sentence)
To me it definitely sounds like oxygen deficiency. Think about it you're taking all that smoke into your lungs leaving not much room for oxygen aswell as standing up quickly. Like you said the blood moves away from your head and is being pulled down by the g force of standing up fast causing the episodes.