To answer the edited question:
Can I say "I've got two glazed eyes"
Yes, it's comprehensible. Saying eyes are "glazed" or "glazed over" means that they're not focussing as expected. This is associated with tiredness or eye-strain. Be aware when using it that it's also (perhaps more strongly) associated with being bored, in general with not concentrating and with not looking at any particular thing. So depending on context there may be some ambiguity whether your work was exhausting or just boring. If you've finished the work and moved on to something else, and your eyes are still glazed, then I'd tend to interpret it as tiredness.
I think it's more natural to say "my eyes are glazed" rather than "I have two glazed eyes".
I can't give you a rule for when English-speakers put redundant numbers in, and when we don't. In this case I think it can go without saying that you have two eyes, and that over-work causes both to be equally glazed. Some people have fewer eyes, but using the plural rules that out, it must be at least two. So there's no need to tell the listener exactly how many eyes you have (although if you had three or more eyes then it might be of interest to mention it).