I'm assuming your doctor told you to maintain a low-fat diet after having your gallbladder removed, so the Whole30 diet (being a higher fat diet) is surely not working for your body in this regard (bile secreted by the gallbladder is what helps break down fat).
A lot of excess fat in the digestive track leads to MAJOR diarrhea, which really is a potential answer for MANY of the old questions posted here.
By no means am I implying this is what's happening to other people, but I did want to put this out there for informational purposes. About a week into Whole 30, everything gave me heartburn. I just assumed it was an adjustment period. By the second week in, I began to have diarrhea in the mornings (usually one or two episodes) and then fine the rest of the day. By the third week, I was having days were I had diarrhea several times a day and was becoming very weak and dehydrated. By week four, I finally went to see a doctor to get blood and stool samples. Apparently my body detoxed a little too well and released toxins into my system that my immune system couldn't fight off. I ended up with an intestinal infection from it. I went the natural route through my naturopath and took a cocktail of various supplements and vitamins and finally beat it after two weeks. The regular doctor wanted to put me on flagyl and cipro at the same time and since I can't tolerate antibiotics, I knew this would only cause me further trouble.
I just thought it might be good to put this information out there for others.