She would be somewhere between 14 and 18 days. It is so upsetting. She said just seconds into the ultrasound that yes she is pregnant, and we were studying the little roundish egg shaped thing, then she went on to look at the rest of her uterus and couldn't find it again when she went back to look for it. She said maybe it was a blood clot or she is just missing it, she did say she has missed them before. She does alot of reprodutive work on TB farms, so she has experience, she just said that since she couldn't find it again she would have to say she isn't pregnant, but please don't sue her if I end up with baby in the spring! LOL! I will try again in a month or so or buy one of the wee foal kits. I also wonder if there are any changes like in mood that could be noticed in a pregnant mare early on?