Ok, I experience 2 types of "eye pain".
1 is connected to LED lights/monitors and causes a stinging pain right behind the eyeball, indicating that I need a break or reduce brightness
2 is connected to migraines, and blocked sinuses, as it is a pressure behind the eyeball rather than a stinging. Mostly indicates the start of a migraine or the need to unblock sinuses during hay fever season.
I have also tore a retina, but there was no pain, only spots in my field of vision and nausea.
Either way, your first stop should be optometrist.
Just my 2c