How quickly does it start
How quickly does it go away once the light is turned off
What are your symptoms
1. LED is the worst for me, even a little LED flashlight can make me feel off-balance. A quick exposure doesn't have long effects but a longer exposure can leave me feeling off balance and nauseous potentially for hours after. I can tolerate some LED phone screens for short periods of time if they use dark mode.
LEDStrain.org is a forum for people with LED based screen sensitivity issues.
2. Blue tinted headlights are terrible. Years ago when I could drive I found that I had to stop driving at night because the blue-tinted headlights would affect my thinking clarity and physical coordination. I would walk as if I was intoxicated.
3. Fluorescent is bad for me but usually takes longer for the effects to kick in. I rely on an old (2007) laptop with a fluorescent backlight. I have the display set to a dark mode, including web sites (using Dark Reader on Firefox). I also have the display dimmed so I can tolerate it longer. I can use the display for 2-3 hours (with breaks) every day but have to wait until the next day before using it again since brainfog increases over those 2-3 hours.
Some fluorescent screens are especially bad. I have multiple laptops of the same make and model but there's only one that I can tolerate for regular use. Another gives me a headache, nausea, brainfog, and coordination problems within seconds.
4. I use all incandescent lights in my home.
5. Sunlight is no problem, even bright sunlight.
I have problems with CRT monitors and TV's too, even though they don't use fluorescent light.
Brightness plays a part. The brighter the offending light, the quicker the symptoms kick in. The longer I'm exposed, the longer the effects last. It takes far longer for the effects to fade than to arise.