Bahahah. Vitamin B12? You use that when you gotta dilute your piss and then have color in it for a drug test -AFD
I believe when you take multivitamins, your piss changes color normally to a bright yellow/neon color. This happened to me all the time when I used to take vitamins. You're fine, your body just isnt used to all the excess vitamins and nutrients you are receiving.