Vision problems

Recently, I began to notice that the vision is not what it was before. The reasons are generally clear - I spend 6-8 hours a day at the laptop. Most of the time - for work. I am a programmer. I did not go to the oculist yet, I am going to next week, but it is clear that my eyesight has subsided weak. What is interested in is - is this a normal phenomenon in the IT environment? Who works with computers for more than three years and still does not wear glasses / lenses?

ps I'm 20 years old. Before 18, the vision was excellent.