I believe this kind of anxiety, as with many anxiety disorders is all rooted in internalization. It's all about 'how you feel'. Constant self analysis brings about the fear and produces the panicky feelings. The mind needs to project away from yourself. If you are concentrating outwardly and not internalizing with self analysis you have the beginnings of recovery from this. Instead of dwelling on how you feel, observe what is around you, the minutest detail. The colour of someones hair, what they are wearing, the paint on the wall, the back of the room . You are then building up a different analysis that is the opposite of self analysis. It's not easy and takes lots of practice.