Eye strain, would I need reading/PC glasses?

Hey there, about a year ago I decided that my vision was not as perfect as it used to be, I explained to my optician that it varies. Sometimes my vision is okay, whilst other times it's terrible.

I ended up getting a pair for distance (forget if that's far/near sighted). Anyway, they only helped a tiny bit and after a few weeks I gave up on them.

I beleive I may be suffering from daily eye strain. I spend most waking hours either staring at a monitor (work & home) or reading. I'm talking hours and hours for several years now.

Anyway, I did a quick Google to see if I might be needing perhaps some glasses for heavy PC use. Some of the symptoms I experience is the inability to re-focus on things once I lift my eyes from my monitor/book (this can last about twenty minutes), terrible vision once it starts getting dark outside when I used to have incredible night vision and my eyes are constantly blood-shot to varying degrees.

I've tried to sort it out naturally by removing myself from PC use but it's just not possible given my work/lifestyle.

So I ask you guys if you think a cheap pair of reading glasses might stop this constant eye strain or wether I need to go a different route.