I included emoji in my password and now I can't log in to my Account on Yosemite
I have had something similar bite me, although mine was easily fixed. I used swedish (åäö) characters for my disk encryption password. This worked fine, until I did a dist-upgrade and had my boot keyboard reset to US QWERTY (using a custom swedish version of capewell-dvorak).The solution for me was to stick on LTS distros.