Those questions are best answered by your eye doctor but I'm glad you did see one and have those tests. Even though some of these conditions like glaucoma and retinal detachment are rare at your age, having these tests to evaluate your eye health is important.
I'm not a doctor but I do know that using the computer especially for that length of time can cause various vision problems as well as headaches, back, neck and shoulder pains. For the physical pains doctors suggest getting up every half an hour to walk, stretch and do some movements of the upper body. My son works in IT and his glasses have special lenses (or maybe coating? I don't know.). So if you wear glasses or contacts, talk to an optician about
this.
But the visions problems are what would trouble me and maybe you need to ask more questions of the ophthalmologist. Call them, speak to the nurse or log onto their patient portal if they have one. Explain about
the continuing symptoms. You might only need to take more breaks to give the eyes a rest - just guessing.
The point is that if these symptoms are continuing, especially after having ruled out eye problems, and if you have tried breaking up your screen time, then you really need to pursue this further.
Best of luck and keep us updated.
