Klonapin will not cause that.. Are you sure someone did not slip something in your drink? Maybe your sugar was low..
That is another thing I considered. Sugal could have been low too. I don't know at this point.
As far as the Benzos, That's really all i could come up with for a reason.
And anxiety? I didn't really have what i normally feel as far as anxiety. It actaully felt more like withdrawl.