Did you get her scanned ?
Not eating is a sign of delivering (nearing delivery) so dont worry, give curd to drink. Yeah and dont chain it let it be free, usually they would find a place during these times to deliver.
How many matings did u do, if you have done 3 matings then the day count could also be the 3rd mating day. Even after 65th day it doesn't show any signs then take to a doc for checkup.