Really sorry this is happening. Even if they don’t think MM is present, there are many differential diagnoses directions they would validly investigate instead of just labelling you with anxiety as the cause of your symptoms..I feel like being anxious with being silenced and basically ignored is justified, especially with your symptoms not being thoroughly investigated at this time.
I hope you get some response from a proactive specialist.. what you’re going through sounds like the system in Australia, where people struggle with this approach for years before getting any legitimate investigations and then get taken seriously. I myself was told repeatedly I had munchausens for years before I was referred for tests, and found to be telling the truth and in fact was not lying for the purpose of receiving attention (munchausens) while those doctors snort derisively right in my face.
I hope you can find proactive care, and get some investigation into your symptoms 🌺