100% what Andrew says, was my experience. Did the LR 5.5 upgrade first, then installed PS CC 2014 next day when it came up. Couldn't edit in PS, when opening files directly in PS 2014 no LR edits showed up.
Tried deleting the presets/preferences folders directly, didn't work.
When you uninstall PS CC 2014, be sure to check the box asking if you want your preferences file deleted as well.
I rebooted after uninstalling, just for the heck of it.
New install fixed the problem.