If you've been recently diagnosed and your bloodglucose levels are going down, you can experience a change in vision. (Sugar distored your eyesight, and your brain corrected for it. It has to get used to not doing that anymore). Get some cheap reading specs to get you through for a week or two, if that is the case. If not, no harm in getting your eyes checked. Better safe than sorry and all.
Have you had your retinal screening recently? What was the result?
If you've recently been diagnosed, it may be due to the gradual normalisation of glucose in the lens of your eye but you should get it checked out by an optometrist.