Hello @Blair ,
some of your symptoms are very similar to my ones.
I have had eyes strain problem since 2013, near 2015 I began to notices discomfort with non-natural light and nervous tick/spasm (especially on right eye). I also had problems with trigeminal nerve that was injured 17 year ago. On summer of 2016 I became extremely sensitive even for natural light (strong dry eye syndrome) and on Autumn I got of bunch neurological problems, tinnitus and sleep problems.
I visited several ophthalmologist and neurologist. And in shortly I found one, that said very simple words:
"You have sitting job, don't do any additional physical exercices, don't walk enough. That causes my blood vessel to degraded. And have a lot of stresses that causes same for vessels."
After that I started to change my lifestyle.
I started with swimming (it was start of winter 2016/2017), its helps me a bit for a day or two.
With warm weather (end of winter 2017) i started to running, and it's add some freshness to my mind (with reliefe for several days).
In May I started riding on bicycle and suddenly in a month my eye dry problem significally decreased (but I have it in decreased state for a year from this moment).
At the end of 2017 summer I noticed that there is no further improvements in my state regardless of physical activity. And I began to experiment with relaxation practices (massage, yoga-nydra, R.E.S.E.T jaw therapy), yoga and breathe meditation. Maybe after a month of meditation I got some small improvements in my state. Further on one of R.E.S.E.T session I noticed some relief in head muscles (on right side) and start pay more attention for this area (head and neck). From that time I have noticed a lot of spontaneously activity in muscles (or maybe vessels) on my right head side.
But after that my practice become irregular for some time.
There should I also say that I tried to make some relaxation practices on winter 2016/2017, especially breathe meditation and yoga-nydra practice, but this practices were biased: sometimes I got better, but sometimes totally awful and I stopped do it for that time. I don't know how it could be explained, but maybe relaxation with bad blood vessels is not good idea. On Summer/Autumn 2017 my vessels became stonger.
At winter 2017/2018 I also noticed that long walks are also very helpful for my state (I walked about 10-15 km. and it was huge for me). Seems on summer 2018 my eyes spasm were ended.
On summer 2018 I passed formal meditation course and from that time I have practiced more regularly. And with practice I began to notice a lot of tension in my neck, especially on right side.
Seems from Summer/Autumn 2018 I became more robust for some led device/light (but not all).
Now I'm running, walking, meditating and riding on bicycle in warm weather. My state is much better that two years ago.
And as conclusion, try to pay attention for this areas and define how it suitable for you:
1. A lot of stress
2. Sitting job and restricted physical activity
3. Overtensioned head/neck/shoulders muscles
I'm not sure that this path is suited for you or anyone else. But if you want try you should find several physical activities that decreases your problem and start to do them more and more regularly from simplest phase to more complex. With time when you notice stopping in progress in your state it worth to switch to or add other ones.