They really are clueless on
withdrawal. This sounds like classic
withdrawal. Nobody can tell you
how long it will last, but frankly, compared with most reports of Effexor withdrawal, if this is your only symptom, you're doing great and will probably be fine in a couple of weeks. In the meantime, try a healthy dose of fish oil daily -- it's said to help with brain zaps, though what you're reporting sounds more like disorientation that is also a very common withdrawal effect.