FIRST THE DISCLAIMER: I AM NOT A MEDICAL DOCTOR. If you keep experiencing this, consult a medical doctor! However, what you may well have experienced is a visual migraine/optical migraine. They are common, and harmless. I used to have them quite regularly, then they stopped for a few years, then I had one again two months after CK. These are migraine type activities in one's brain, without the headache. Look this up on the internet. There's other names for these, I don't remember what. The prism type spots in your vision are called "scintillating scotoma," and they are the classic symptom of these. What a mouthful!
After I experienced the one in May, I did gradually develop very mild double vision, and other vision problems which appear to be related to my vestibular (balance) system.
I'll bet you'll read the internet, and be quite relieved. Important note: visual migraines don't last very long - 15-20 minutes at the most. If you experience stuff like this that is ongoing, you need to call a doctor promptly.