Your high bg levels could well be the reason why you have problems with your feet, also if these problems have only come about since starting on the statin you should mention this to your gp, they may stop it or change you over to an alternative statin.
The vision problem is a classic symptom of high bg, when levels are raised the lens of the eyes swell and this makes vision blurry, rather than go back and see your diabetes nurse why not book a appointment with your gp and get a check-up and explain all your problems to them.
Good luck!!!