I spend a lot of time on my pc but always with good light. A couple of days ago I noticed that my eyes took a long time to focus and when I look at things at long range it all merges into one, I can see the outline of leafs and stuff but not the detail. Also, when I drive along in the car I can't see number plates or wording on signs perfectly focused. All I see is the outline of the word and guess it. My eyes are dry and hurt whenever I look at things in a distance. When I look at things it focuses perfectly for a second then unfocuses quickly and I can't get it to refocus unless I close my eyes and then open them again and it does it all over again. I have dry eyes which water a lot of the time making it much worse. I came back from holiday a week ago and this has only happened in a week of using a pc which is unusual as I spend a while on it a lot of the time before but nothing happened. It came on so suddenly so I don't know what it could be. I had something very similar but with my ears and it went off with some ear drops so it might be the same with this. I want to be a pilot but since I can't focus in certain patches at certain distances I don't think glasses will fully fix it. I am going for an eye test but I want to know what I will expect.
Your symptoms do suggest a refractive error that may well need correcting with glasses, but it is unusual for you to suddenly have the problem. Although it is worse when you have been on the computer this will not be the cause. With your eyes being dry you could also have a problem on the cornea with the surface becoming superficially damaged and also causing the reduced vision. You should certainly have an eye test, but in the meantime try using some lubricating eyes drops that you can buy over the counter at the pharmacy or opticians. Use them frequently and see if this helps the problem.