True, proper for you, "reading" glasses are likely too strong for computer use. You need something weaker than a standard "reading" prescription unless you are working with hand held displays (phones, tablets, ...). That said, you can start with off-the-shelf reading glasses from the drug/dollar store. If you do, start with the weakest, ~+1.0d.
Also, it is highly unlikely that using a computer screen is the cause of your vision change. It is quite normal for vision to change as one ages. Check your driver's license and if the DOB is before 1980 then age is the most likely cause. You should see an eye doctor, optometrist or opthomologist, and have your eyes checked to be certain that there are other issues involved.
I've worn eyeglasses for over 60 years (my DOB is way way earlier than 1980). I have significant myopia (nearsightedness) and moderate astigmatism. I also have presbyopia (narrowing of the focusing distance adjustment range, the primary age related vision change) which leads me to have different prescriptions for distance vision and close vision. I work with my eye doctor to get a prescription for more of a middle distance (~ 3' or 1m) instead of the typical arm's length reading distance. This is to target usinging a computer screen. Since I work with a large dual-display setup daily, I have dedicated middle distance glasses in addition to a separate pair for distance vision instead of bifocals. I have begun to also use some pince-nez generic reading glasses at +1.5d as an add-on boost for my distance glasses for reading at arm's length when I'm not wearing the "computer" glasses.0