Shoe, I use Bioceuticals Babybiotics 0 - 3months (they aren't in that link, but you can see the blue label of that range to look for). In my last life, *before children* , I was a naturopath and I still have access to the professional range. But I do believe you can get them from a health food store, they'll be behind the counter or from the person who works in the store (they're often a naturopath).
Also, I just remember that thing called a "nursing strike". It often happens when a baby is also fed by bottle, as bfing is hard work for them and bottles are a breeze. They choose the bottle over the breast, and wait for that apparently. I'm going to be on the lookout for it when I introduce expressed milk down the track.

Jodie, I envy you!! Looking forward to those days...

Apparently bf babies can not poo for a month and it be "normal"! I don't know about that myself, but that's what I'm told.