Thanks for writing your query.
After reading your post, it seems that you might have suffered from Vasovagal attack.
In this blood supply to the brain gets decreased as a result of sudden fall in blood pressure.
You should lie down with head end lower than the feet whenever you begin to feel the symptoms. This will increase the blood flow to the brain and cure the symptoms immediately.
You should get yourself clinically examined.
Following investigations will be helpful :-
1. Blood pressure and heart rate
of head and neck.
4. Blood sugar levels.
I hope this is helpful to you.