As the title says. When playing blitz (3 to 5-minute games), I experience eyestrain after 10 or more games. After that, I start to blunder. I get tired too fast.
In our area, it seems to be only me who has this issue because my opponents can play a whole day without signs of exhaustion. Their plays don't change while my play changes after few blitz games. It is like starting from Elo 1850 then after few games it seems that I am playing like in Elo 1500-1600 while my opponent's strength and any other players' strengths in our area are the same the whole day.
By the way, I work online for at least 10 hours each day Monday to Friday. I play only on weekends. I have computer eyestrain too (a different case, not OTB chess eyestrain). But on weekends I still get eyestrain even when playing OTB only and not using a computer. I get enough sleep on Saturday, so I should not get eyestrain on Sunday when playing OTB, but it still happens.
How do I solve this issue?