Questioning my FND Diagnosis and Feeling Hopeless

I don't feel like my diagnosis of FND is correct. I feel like all my doctor's (PCP, neurologist, and psychologist) were dead set on what I'm feeling is caused but anxiety. I had to fight for minimum testing like routine blood tests, and MRI's even though my symptoms alone validated the need. They came back normal so I was diagnosed with FND that's triggered by anxiety. My anxiety is under control and my symptoms don't follow the same pattern as my anxiety. My symptoms are now continuing to get worse. The burning pain I experience in my arms and legs can get so excruciating. Right now I feel numbness and tingling in my head, arms, and legs. I feel so sick. I just don't get it. I'm trying to find new doctors to get a second opinion but I feel so hopeless and alone.