Yikes. It sounds like a whole lot of bad things could be going on.
 
First, I'd change the litter to one she doesn't eat.  Is this clumping
litter?  If so, and she is eating it, it is probably clumping in her
stomach.
 
Ferrets can't bring up a hairball, like a cat can.  If it doesn't come out
the other end, it has to come out by surgery.  What did you mean, you put
vaseline on her lip?  Did she lick it off?  If not, this will have no
affect whatsoever.  If you are concerned about a minor blockage, if there
is such a thing, try giving her a hairball remover once or twice a day
(vaseline will work as long as she eats it).  If you use a tube of remover,
try an inch long strip in the a.m.  and p.m.  for a couple of days, then
once a day.  Of course, watch the poopies.  If she is not pooping, and
constantly throwing up after eating, GET HER TO A VET RIGHT AWAY.  If food
isn't going in, or coming out you've got a real problem.  You might want to
get her some food that wasn't manufactured in the same lot as the food you
are feeding her now.  Maybe there is something wrong with the batch.  Watch
her closely, and if you are unsure at all, get to the vet right away.
 
Lara
[Posted in FML issue 2569]