I finally found the answer!
I found this just Googling, because after talking to a specialist I came away unconvinced. Now, just 5 weeks after starting, I’m really comfortable and so pleased with my progress. I’ll complete the recommended 12 weeks and carry on just to make sure the improvement is permanent. I really don’t want to go back to the anxiety and discomfort I’ve experienced these last few months. And I’ve changed my specialist.