Pregnant/ or Not?

Question
I have a 15 yr old mare that has been bred once before 3 years ago. From June- November 06 she was leased out. Now, understand she is a fat girl, hard to keep weight off of her. I have noticed that she is larger then normal and her bag is half full with milky/clear fluid. Her milk vein is very full. Her butt muscles are kinda relaxed and her stomach may have been moving (it could be a stomach ache or my imagination, though she was eating). She has been rolling and I honestly can't say when she was last in heat, even with a young stallion around this spring. I am experience with foaling, but due to moving all of my books are packed up.
My questions are: Do you think she is prego or just fat?
If she may be prego how many months?

Thanks

Answer
Hi Emily,
          Without seeing her I could not tell you if she is pregnant or fat. From your description though, there is a good chance that she is pregnant. The signs you are describing sound as though she has a two weeks to a month to go before she foals. If she was in with a stallion during the months of August or September then you will be having a foal soon. To be sure you can always have your vet palpate her.

Good luck.

Lisa