I have a mare that the last time I saw her in heat was the 25th of August 2016. She was with the stallion in the pasture. I checked her again 3 weeks later and there was no sign of her being in heat so I assumed she was/ is in foal. I started giving her some mare and foal feed about 6 weeks ago, so she is definitely fat, not sure if it's foal or feed. I would assume she is in foal except there is no sign of udder development. Is it possible that a maiden mare wouldn't bag up before foaling? or should I start to get ready for disappointment?