I have been having difficulty breathing, with a feeling like I can t take a deep breath and difficulty to complete a yawn, my chest feels like it s not expanding enough for me to get a full breath of air, and my back hurts in my thoracic spine. I was diagnosed with panic disorder/ anxiety and was Rx d Paxil 20mg. I began to have teeth chattering and did not feel right. My MD switched me to 100mg Zoloft and the teeth chattering has continued, as has the shortness of breath, which does not always change with physical exertion. He did not do chest X-ray, and my blood results, thyroid and EKG were normal. MD seems to think the teeth chattering is the result of increased anxiety, and not the medications, but I disagree as I haven t seen improvement in any of my symptoms. What might be causing this?