I still have the vertigo and it has been a week since it started. The doctor mentioned about the blood pressure going low and then it went really high until it stabilized. But the verigo hangs on. There is no telling when it will dissapear.The doctors gave me some Epley manuevers to do. It supoposedly helps with the verigo.
Has the vertigo happened since then? If not, more than likely your carotid artery was compressed long enough that part of your brain had the oxygen shut off or severely restricted for a brief time..If both sides are compressed (like in a wrestler's "sleeper hold") you lose consciousness...Another thing that may have happened is your vagus nerve (big nerve that connects to your brain, carotids and heart) was stimulated which may have caused your pulse to slow and blood pressure to drop, created low oxygen to the brain, and thus, the resulting vertigo and vomiting...It takes a moment for the blood pressure to recover (up to 10 minutes in healthy people) so, it may have been missed if it was low briefly...
If this was the case you may be one in the small minority of the population that has an especially sensitive vagal nerve reflex. If so, in your future, if you take any medications (like beta blockers) that hold your blood pressure or heart rate down, be aware that, when having a lengthy bowel-straining episode (Yes, I mean pooping -don't laugh!) you have a higher chance of passing out because of your blood pressure and heart rate dropping too low...Just so you're aware...~MM