We have a mare that "looks prego" She just has a hay belly. lol
I'd definitely work on haltering her now, and letting her know it's OK to be haltered, and that you're not going to hurt her, especially not knowing if she's in Foal.... Sorry, but, it it were me, I couldn't help but to be out there staring at her, and loving on her, after the first few.
Hard to tell by looking, especially, since she is such a big girl. She has the bone structure like one of our appaloosas.... Very big!! lol
By the way, even underweight, I still LOVEEEE the conformation of this Mare. I saw your other posts.....
She has AWESOME bone structure, and her hips are big, and powerful! I also Love the coloring. Nothing beats a Leopard!!