Put some lube in your eyes, you are experiencing friction between your eyes and skin, obviously this is the best advice anyone can give you.
Aside from that sarcasm, make sure your screen isn't too bright, don't have your face right at your screen, take breaks from playing osu.
Aside from that sarcasm, make sure your screen isn't too bright, don't have your face right at your screen, take breaks from playing osu.