Aileen,
 
It does sound like insulinoma to me, especially with the low blood sugar
reading.  When my Alfalfa first had a hypoglycemic episode, he stumbled
around like he'd had a stroke, collapsing on one side when he tried to
walk, with his head held to the same side.  Was she drooling too?  That's
another clue, as you probably know.  If it happens again, try giving her
some honey or corn syrup or Nutrical, rubbing it on her gums and tongue.
If that brings her around, then you have your answer.  If not, then it's
something else.
 
Best wishes to Noel,
Nancy and critters
[Posted in FML issue 3684]