I have the problem of waking at 5-6 AM, as well, and feel an anxious feeling in my solar plexus. What works best for me, and it works pretty quickly, is to use acupressure points for hypoglycemia. After holding just a few points for about 2 minutes each, I can feel my whole system relaxing again. While I hold the points, I also do a yoga breath called the "ujai" breath. Very easy to do. If you don't know what the acupressure points are, I can list them for you, and then you'll have to go to a website such as Yin Yang House dot cm to learn where the points are so you you can press them. It really works well, and often, I can go back to sleep til about 8:00 AM. Let me know if you want the list of acu points.