bummer about the carrot cake! If you want to challenge soy or dairy, it's usually more accurate if you try something closest to the 'purest' form. So soy beans (edamame) or tofu (soy milk has a lot of additives) for soy, or milk for dairy. Also, my doc said that dairy can take a while to clear both of your systems, 4-6 weeks sometimes, so even if you're being really good you might get a symptomatic diaper but it's just some old stuff flushing out. Also if you have frozen expressed breast milk you may want to toss it, since you probably had dairy/soy in your body when you pumped. I'm glad she's doing well!
with teething, my DS started getting really fussy on the breast. I attributed nearly everything to his MSPI at that point, so I thought "Oh no! he's in horrible gastric pain due to my 'tainted' milk!" I was really freaking out about it, he would pull off and not eat and I was getting engorged... well, one of my friends asked "is he teething?" I thought she was surely wrong, since like I said I thought it was all about MSPI. Well, I looked in his mouth and saw a tell-tale bulge on his lower gum just the size of 2 teeth. They cut the next week. But some babies stealth-teethe and you don't notice til you feel the sharp edges when nursing!
I don't know which part of the country you're in, I'm in California and Safeway has a brand of margarine called Nucoa which is MSP free. It has soy oil & lecithin I think, but those are fine since they're fats. It states right on there that there is no milk, and I didn't see dairy at all in the ingredients. Some have said Fleischmann's but I haven't seen that in any of my stores. I heard you can use Crisco for baking, haven't tried since I've used the Nucoa when I've made cookies. Just double check the butter-flavored one for casein or whey.
