Read your post about the bugbite resulting in a mark resembling a bullseye.
That sounds the the bite mark from a deer tick.  The resulting bullseye mark
would also be the first clue to possible Lyme disease.  Lyme disease can
cause severe joint problems as it progresses.  If caught early it is easily
treated.  IMO I would not wait until Friday to take Casey to the vet.  See
if you could get in earlier and have the vet do a blood test specifically
for Lyme disease.  If it comes back negative wait a little then have it
repeated.  The earlier Lyme disease is detected the easier to treat with
antibiotics.  Hope this helps and prayers be with you.
 
Ferret hugs,
Donelle
[Posted in FML issue 1950]