A switch to Amitriptyline might do the trick. Worked for me. Remind me, did you fail Ami? It is a stronger anticholinergic and therefore vestibular suppressant than Nort. 20mg sorted all my issues with video and computer screens.
Oh you did, hmmm. Amitriptyline VS Nortriptyline need advice - #9 by Suffering
Btw my light issues were the same. A mix of daylight and artificial light was always the worst. It made me feel a kind of discomfort in my forehead, most strange. Evident even in cafes during the day with those lovely vintage lamps glowing 