Ive been down this road before... lots and lots of dead presidents, but I had the money, and my buddy was worth it. Ended up having cancer and supplements kept him going another year when vet only gave him a month... had vet come to house to send him on his way...

You may be tight on money, but I can tell you this, nothing haunt you worse than thinking what if you had spent the money, at least to find out what was wrong and if easy fix. Humans will always get some type of help, fur buddies rely on us...