Hello dear...I have gone through your post in which you have mentioned an incident when you felt dizzy, saw white spots
and felt faint.
All these symptom suggest that you might be having Hypotension
(low blood pressure) or Hypoglycemia
(low blood sugar
There is nothing to worry...visit your Doctor once & get your blood pressure & sugar levels checked.
Other than that, eat healthy food, exercise regularly, avoid stress, get good sleep, think positive and stay happy.
Wish you a healthy life.