Yes this happened to me to. I ended up with a nutritionist who sabbotaged every effort to show that I had candida. Was she an unbeliever or just incompetent - its hard to know. But she certainly had made up her mind that I didn't have candida. I lost 6 months of healing effort because of her incompetence.
You have to understand that there are a lot of stupid ignorant people out there, and some of them pose as health practitioners (both alternative and conventional).