Welcome to the forum. I hope you find our folks to be friendly and helpful. As you've already read, the only sure way to tell if your mare is pregnant would be to have a vet out for palpatation or an ultrasound. That being said, when you get closer to time (if she is pregnant) you should be able to feel the foal moving and then of course the waxy build up, or even the milk, but that doesn't happen until end stages.
If your mare was thin or undernourished, this could be a dangerous situation for her and the potential foal, especially without knowing the history of this mare, as in, how old is she? Is she a maiden mare, etc.
You might want to do an internet search for vets in your area, I'd be suprised if there were none available. Good luck!
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