Dear Friend, One piece of advice I can give to you is to say, "don't give up!". Don't let them tell you "it's probably just depression" and not look further (if that was the case). I have been around the health care business for a very long time, and know for sure that the health care system is not known for always taking patients seriously when they have persistent problems. I know there are wonderful, caring and thorough health care providers out there, but I also know that a lot of diagnoses are missed when the symptoms are subjective and the patient has a lot of different manifestations of a particular problem- such as is seen with Celiac disease.
So, calm down, take a deep breath and start "logging" everything that is happening. One thing is to focus on the starting point of your diagnosis, and be specific in logging your weight (example:from what date to what date did the loss occur), your symptoms and any "changes" that might have occurred, AND your food intake, including your calorie count. You can do this.. there are lots of tools on the web that will help you. But,you need to get some real data to show your MD. For instance, did you perhaps eat foods, or introduce new products into your house, etc.? Did you eat out some place that you felt was safe, but might not have been? Celiac disease can truly affect you in a lot of ways, and it can be triggered to give more symptoms in ways you may not suspect. So, LOG daily- your diet, your weight and your symptoms. If you are only taking in 1000 calories a day and you encounter gluten in an unknown source, you wouldn't even be getting the benefit of that low calorie count, so of course you would lose weight. You need to have specific information to show the MD so that he/she can analyze changes more accurately. Sometimes they just don't ask the right questions to know how to relate the problems a patient is experiencing to the real culprit. (example, not enough calories AND gluten exposure would of course be a significant problem).
But, if you decide to seek another opinion, make sure that you go to a different practice and different MD if you want to do that. Partners in the same group have been known to not oppose a diagnosis of another member of their group- even if the specialty is different (example- Internal Medicine says one thing- and the consult is with a Gastroenterologist in the same group). Of course I know your insurance coverage will be a big factor, but try to get all your facts together prior to changing doctors as well- if that is an option). Just another tip.. you have the right to have the results of all your tests explained to you. Insist that you get that.
Finally, I would say that depression is normal, to some degree, with anyone who is diagnosed with Celiac disease and is trying to cope with all the restrictions, explanations, and generally lack of understanding that is encountered from others around you. But, depression should be managed and treated- As it IS a real diagnosis and is treatable!- it just shouldn't be the diagnosis dumping ground for any new problems that occur. New problems (such as a profound, continued weight loss and NEW symptoms) should not be ignored. So, make sure that you understand the final diagnosis and treatment plan, and make sure that you are taken seriously and have had your treatment plan explained to you. AND, be sure that you know exactly what to do to make yourself a true partner in your health. This website (which I just discovered while trying to find ways to help a family member who was just diagnosed) seems to be a great place to get not only good information, but also good support. Good luck and take care (See, you're not the only one who had a "long" post!)