I had the same thing happen to me. It started a year ago, my head went all funny and I started feeling pain in my head, stomach and other organs. I thought I had a tummy bug that kept reacurring. It got worse and worse and I lost 15kg in a few weeks. No one put it down to menapause because of the weight loss. I ended up in hospital for a week and had every test possible done on me, but everything came back clear and I didn't know what to do next. I couldn't go to work or anything. I then noticed that the symptoms were accompanied by hot flashes. They tried me on HRT but that made things worse. I've ended up on a product called Amberen which has helped immensely but has not completely got rid of the symtoms even on a double dose. But it has helped me live life sort of normally! FODMAP diet has also helped heaps, along with breathing techniques and contemplative techniques for the mind, and walking for excercise.