You can mix that baking soda with some vegetable oil, a good size handful of baking soda mixed with about 1 1/2 cups of veg. oil IF you think she is boated. Left side bulged way out and seems to be in pain. They can die from bloat. Unless you are aware of how to do it you will need to have a vet release the air via an incision in the high left flank area. This is used only in case of a true emergency bloat problem. Otherwise if no obvious signs of bloat and it could possibly be calcium deficiency, I would immediately get some CMPK liquid if you can find it, if not get the gel and mix it with some gatorade to make a drench and get it down the doe. If she is unable to swallow you can tube her or you can get the vet to give her calcium injections. You could give her some propolyne glycol also. Follow up with your vet if you see improvement or get more info on here about her diet at this stage of pregnancy. If you think it was poisoning from eating something toxic, you could try getting some activated charcoal down her and give her some fluids orally and get a bag of fluids from the vet and put a couple bubbles of fluid under the skin about the size of your fist over each shoulder to try and process the toxins out of her system. I hope she is ok.