Your eyes may feel rubbing because of the eyes infection from the invisible bacterium. You should take great notice of. It may be caused from your mentality. But you should have the good rest for the eyes now, not sitting in front of the computers for a long time. In addition, you could also use some eye drops to clear the eyes. It is workable and effective.
You may be suffering from dry eyes. Feeling foreign things in your eyes is a symptom of dry eyes syndrome. When a person has dry eyes, there is a lack of tears for his cornea. The protection of cornea, that is, a tear film can't be formed. Then your cornea is exposed to dust, bacteria and sand in the air. Your cornea may have been scraped now. You need to drip some artificial tears or eyes luricant.
Maybe there is something in your eyes, but as you can make sure that they are clean, we can get some other assumptions.
First, I wonder if you have a bang ahead of your forehead. Because the hair around your eyes may sometimes get into your eyes and cause your eyes feel chronicly uncomfortable. So what you need is a hair cut.
Secondly, it may be a sign of dry eyes. You have to pay more attention to protect your eyes. You should have a timely rest when you are using computer, you can just see through your windows something faraway. Proper exercises outdoors may help after sitting for a long time, which because exercises can improve the condition of blood provision to fast the metabolize. Eye drops can also relief it. A healthy diet is also necessary.
If things do not get better, you'd better see your doctor.