"Monovision" in the in-eye lenses is a very common choice for elderly patients having cataract surgery. There may be a period of adjustment, which you wouldn't have had.

I am not GP, but I don't have a problem with a single contact. What I find really neat is after hours of just one, the vision in my other eye is improved for a while; I can actually see decently from the non-contact eye when I remove the contact.