Are you sure it was the lights that triggered it? That happens to me a bunch (but I only actually went unconscious once) where I lose my sight, feeling in my legs, and eventually my sense of balance and position. You can kinda feel your head get colder but once you get lower to the ground the blood rushes back. I think it's usually triggered when I stand for extended periods of time or concentrate hard on something. I hear people talking about getting a little dizzy and possibly having darker vision when they stand up after lying down for a while, but this is way bigger than that
If its any consolation, I did go to a doctor and they said nothing was wrong! yay