Many reasons.. Refractive error Computer vision syndrome Dryness Digital strain Not correct posture Have you ever got your eye tested??

Hello This could be due to computer vision syndrome Try A. Get eyesight checked B. Cold compresses C. Use lubricating eyedrop Consult local ophthalmologist

It is called digital eye strain or computer vision syndrome....make sure posture is good, there should not be too much reflected light, computer should be down in a book holding position, take breaks , follow 20/20 /20 rule Every 20 mins, take break of 20 secs , blink 20 times or look in distance. Blink more often, use a lubricating drop, some supplements, maintain sleep pattern ... If does not help , check for any refactive error from Eye doc