I know I have experienced these same symptoms, and I'm sure many on this board have as well. I bought the book "Hope and Help for your nerves" by Claire Weekes. I highly recommend it. Some advice she gives, is when feeling tense/anxious is to let it happen. Easier said than done, but let it happen. Also, when you are in a state of calm, try to make yourself tense/anxious. I couldn't do it. The book has done wonders for me.