I just wanted to put my hat in here since this seems to apply heavily to my situation.
I have to have gluten free shampoo, conditioner, body wash, chap stick, etc. It wasn't all at once, but started in college for me with my severity hitting a new peak. I am extremely sensitive to gluten/wheat. When I speak to newly diagnoised Celiacs I do express caution because of my own issues. I had a shampoo that had wheat germ in it. As things progressed I began to have "shaking episodes" as the neuro guys put it, or awake seizures. I also began to get rashes on my skin on my upper arms as well.
My celiac has progressively gotten worse over the 13+ years I have had it. Now, I also have to say that I cheated severely for a couple years in my high school years, which I think has affected my severity. I get tested almost constantly and travel to many specialists. I am one of the more rare severe celiacs that have to watch everything.
Basically, for "new" celiacs I wouldn't worry about it up front. Just keep it in the back of your mind that if you do not adhere to the diet and doctor recommendations there are possible severe consequences. I was dumb enough not to listen and have to live with what I did as well as my loving supportive husband.