I am in exactly the same place as you, 6 months since I noticed it, and my mind has had me suffering from every illness that could be remotely associated with it. Totally exhausting. The worst is waking up and immediately experiencing that unwelcome sense of panic and terror. Lots of tests and nothing so far except a low iron count in the blood. I live alone and have poor eyesight so reading anything more than a few forum posts is difficult so distraction is hard. Valium seems to take the edges off the panic but (understandably) my doctor is unwilling to give me a repeat prescription. All the doctors I have seen recommend propranolol but that is a beta blocker and I would totally freak out on them. It is comforting to know that I am not alone, but as I'm sure everyone knows that the comfort and reassurance never seems to last. It's all so terribly depressing.