Goat with Diarrhea and other questions

So we got goats (2 2-year old, first freshening does) for the first time 2 weeks ago, and the first few days they weren't eating, always crying, etc. They are from a farm with around 50-so goats, so were extremely homesick the first week. They have somewhat settled down lately (thankfully), and while we get their permanent shed and fencing ready, they are temporarily housed closer to our house, and are taken out to forage for a bit every day while we are outside.

They each produce on average about 2.5 pounds each milking (twice a day) and get 6 cups of grain each every milking, which some days they do not finish. They also get free-choice alfalfa hay, free-choice minerals and baking soda, along with a handful of beet pulp, calf manna, and sunflower and pumpkin seeds during milking.

Their poop was looking good, one had very nice berries while the other had more clumpy berries. But today one has gotten diarrhea, with no visible berries at all. Two theories I have now is 1) we let them out for too long yesterday, leading her eat more grass/brush than she normally would and upsetting her stomach or 2) she ate something toxic. She kept going back to eat our needle holly and took a bite of azalea. This would also explain why she got diarrhea and not the other.

So, are there any ways for me to check if it is one or the other? What are other symptoms I should be looking for? Especially since I haven't had the goats long enough to know what usual behavior is like for them, and anyways it is our first time with goats. Should I just let it be one day and see if it gets better? She is still eating hay and drinking some water, and is not acting lethargic or anything.

Sorry for the super long post.

There are several factors some of which you have already mentioned however I strongly recommend you get a fecal analysis done on both goats asap. The time frame that you have had them and they are newly fresh spells out parasitic bloom.
Although it may clear up tomorrow and everything is back to normal which would indicate something the one ate the fecal is still really important.
Pregnancy hormones during the last part of gestation causes a parasites to multiply faster. Add to that they have been moved to a new home and the stress of the changes will cause huge bloom.

Congrats on your new goats BTW!

I am curious, is this how much the breeder was feeding in feed? That is alot of feed for a Nigerian. Our standard goats get that. Our nigerians get about 2-3 cups maximum am/pm

Baking soda is unnecessary and can long term be very bad for them.

Thank you! Yes, we have contacted a veterinarian near us that does fecal tests and we will definitely get one done ASAP. I have never heard of parasitic bloom, will read up on that some too. They are Nubians, the breeder said she lets them eat 8-10 min. We were worried about them losing weight, especially with the stress of moving, and from what we saw online that was the figure we understood as standard. Could you elaborate a little more on why baking soda could be bad for them in the long term? Just curious, as all of this is really new to us.

My apologies, I thought you mentioned Nigerians. Silly me.

I was trying to pull up the article for you but it was not loading. Basically goats make their own and when we interfere that causes them to get thrown off. It was really started by the dairy cattle industry because of heavy grans and issues with acidosis. Hi grain diets may require it. If this has been successful for your breeder then stick with it, a good breeder knows their goats.

Parasitic bloom is when the parasites multiply rapidly, usually due to hormones, stress, move, sickness.