Stall stress? Need some quick advice please!

When I got to the barn this morning everyone was getting the horses turned out, but my youngest mare was in her stall still. I went to get her out and she was dripping with sweat. It's 40 degrees

They said she was pacing her stall but she has paced before without her getting herself that worked up. She's on Safe Choice and CoolCalories (basically rice bran).

One of the other owners suggested a supplement for mares that have bad heats. But if she's never been like this before, should I not get the vet out?

Does she just start when the horses are being turned out? If so, maybe her being one of the first turned out would help. She may just be getting nervous that she might be left in, or she's just that excited to go out.

Yes she most definitely wants out. She's usually the last one out because her turnout is the closest to the barn and the others are concerned she will try to talk to the other horses as they go past to their turnouts.
But she's never got herself into a state like she had this morning.

I would turn her out first, or as one of the firsts, to save her the stress. If she talks, she talks. She's not really hurting anything right?

Yeah, I don't get how "talking" would hurt anyone

Are you sure its just anxiety? Make sure there isnt a health issue as well. I know when my mare coliced she broke out into a sweat in 30 degree weather because she was so in distress. Just make sure she's all okay before you turn her out in 40 degree weather

I've been going out and checking on her every half hour or so, she seems fine. I want her turned out first but the others are intimidated by her. She's not scary or pushy, and is even the lowest on the pecking order.

If she gets that stressed out again I'm going to be concerned not only about her sanity but ulcers.

Who is intimidated, the people putting her out, or the other horses? I generally turn horses out to pasture in a certain order due to how they all get along with each other. It makes it safer for all concerned.

The people are. She's turned out with a gelding. She's always been bottom of the pecking order, so it's not really other horses that would be intimidated by her. She's one of the biggest horses in the barn.

Poor baby, she is probably just getting impatient for her out time. I can't imagine it being a heat cycle problem since they start to cycle less or not at all this time of year.
I would be concerned for her getting all worked up as well. Can you ask the caregivers to turn her out sooner? Can she be on 24 hour turnout? Maybe she would be more comfortable with that.