My friend has the chills, shaking, and nausea.  Thought it was just the flu when she told me. Until she told me that she has a feeling in her chest like "squeezing near her heart and feels like someone is sitting on her lungs".  Could this just be stress/anxiety?
Thanks for your question on Chat Doctor. I can understand your friend s situation and problem. We need to first rule out lower respiratory tract infection (LETI) - pneumonia in her case. Because fever with chills (shaking) and chest heaviness us seen in pneumonia. So consult doctor and get done clinical examination of respiratory system and chest x-ray. If chest x-ray is normal then no need to worry about pneumonia. Stress and anxiety can be the cause for these symptoms. So consult psychiatrist and get done counseling sessions. Try to identify your friends stressor and start working on its solution. Don't worry he will be fine. Hope I have solved your query. I will be happy to help you further. Wishing good health to your friend. Thanks.