Does it hurt to read this?
Maybe you scratched your cornea. Or, maybe you are reading too much and staring at the computer.
I had a problem like this when I was in 8th grade. It was hard to keep my eyes open and they kept tearing. I'm not sure which one hurt, it seemed like both of them were sensitive. That only happened one time in my life and it lasted about 2 weeks.
Get some saline solution and flush them and keep them closed for a while.
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As long as man continues to be the ruthless destroyer of lower living beings he will never know health or peace. For as long as men massacre animals, they will kill each other.
-Pythagoras