I often have sore muscles and I can't think of anything I've done to cause the soreness. I believe that it is due to the stress and tension of my anxiety. I also have been diagnosed with GERD. It can cause you to have to clear your throat often and have heartburn. Mine causes me to have frequent sore throats and sinus problems as well. The chest discomfort could be from GERD or anxiety. When my anxiety is "acting up" I have chest pressure, discomfort and feel short of breath.
If you do have GERD it might help to eliminate caffeine, alcohol, spicy food, tomatoes, etc. from your diet. Try not to eat large meals or lie down too soon after you eat. I try not to eat after 6 or 7 at night.