Is it possible that you are spending a lot of time in front of a screen? It can be a monitor, a TV or any other digital thing that emits light
The problem with that is that screens (monitors) emit a lot of Blue Light
That can be the cause of dry eyes or why your eyes are tired all the time, it can also really reduce the quality of sleep that you get
To fix this you can download a program like Iris.
It specializes in saving your eyes and making you feel better while in front of the computer
You can read more about Blue Light and Iris here: