Ella in Foal?!?

I went out to the barn on Sunday, it was a snowy, cold day. Brought Ella in for a good grooming and to be turned out in the arena so she could warm up and stretch out. She was her usually self, quiet for the most part with a bit of attitude (that I honestly don't mind, its nice she's a bit sassy). She had been wearing her rain sheet to keep the snow off, but as I noticed she was a bit sweaty around the shoulders and neck area I decided against putting it back on. She's generating plenty of internal heat, whether it be hay or foal I am not entirely sure. So, for these reasons she is not wearing her blanket. 

Plus, I happened to notice how round she was. I am still not 100% sure, but I do know that 'if' she were in foal, then her due date is around the end of this month (March) or beginning of April. 

I have been trying to check for signs that she is, such as: 

• Swollen udders
• Dropped belly
• Wax on nipples
• Dripping of Milk
• Milk streaks down hind legs
• Change in attitude (restless or tired)

It's extremely hard to tell by just looking, especially as I only just got her in October - so this is our first winter together and I'm not familiar with whether she typically gets a "hay belly" or not. Nor am I familiar with how she carries a foal. 

She's had a couple foals in the past and this isn't exactly 'new' to her ~ BUT it's certainly 'new' to ME! I could pay to have a vet check, but from what I understand the vet would confirm "yes" or "no" that she is to have a foal and wouldn't be any better at guessing the exact due date. I have the dates of when she had her last foal and when she would have been 'covered' etc. So, she is either going to have one or not and if I wait and see ~ the question will answer itself. It's the waiting and not being certain part that is hard! 

Here is a BEFORE picture(s) and a NOW picture(s). The before pictures are from the previous owner who rescued her from going to the Meat Buyers along with two other Mares (who have been confirmed by the vet to be in foal). They were taken in October of 2012 and the now pictures were taken yesterday, March 17, 2013. This might help determine whether it's typical for a Mar to put on that much wait in a 6 month time frame. 

Before (3 pictures) October 2012:

Now (3 pictures) March 2013:

I could have a vet check, but from what I understand the vet would confirm "yes" or "no" that she is to have a foal and wouldn't be any better at guessing the exact due date. I have the dates of when she had her last foal and when she

Also, I took a picture of her udders, when I checked (to me) it appears as though there is wax on her nipples. Might not be able to see what I'm talking about (white dots) in the picture clearly, so I have also included two sample pictures from the internet that are clearer so you can look at them and see what I'm referring to and then go back and look at Ella's.

Ella's Udders (2 pictures): 

Internet Sample (2 pictures):

As you can see it is hard to tell. I'm not sure, but am keeping a very close eye on her and am lucky to have others doing the same as well. 

Here are some MORE PICTURES of Ella from March 17, 2013 you can check them out ~ they will offer different angles and a different perspective having someone standing next to her.