See if you can find an alternative type doctor that believes in candida. You need one that does a live blood cell analysis, that is how I was finally diagnosed with candida after going to doctors for two years.
I too, was given the "it's in your head" speech along with a script for Prozac which I promptly trashed.
You have every reason to be upset. You have been in your body for 33 years and nobody knows as well if you if there is something wrong with your health. Study up on the cleanses for bowel,liver and kidney and start doing them, they will help.