I had a re-do on a root canal on my upper right no.2 molar last one in back, wisdom teeth have been extracted. X-rays showed a cyst or pocket of infected area, or something. Re-do was successful though pocket area did not drain. I have had trouble focusing with my right eye before re-do and since, Could that affected area be pressing on a nerve or something causing my right eye to be straining?

Were you given an antibiotic to clear up the infection? I'd suggest you talk to the dentist who did the retreat he may want to refer you to a specialist.

You need to go back to your dentist now... cranial nerve impairment (like those that cotnrol the eye) may be a serious sign of a bad infection.