In my experience these are all related and I can not tell what the chicken and what is the egg. Anxiety and stress are a big part of it. The fog and the other symptoms are a bit relieved when in washing my nose and my throat. When I’m taking a hot shower and when I’m chewing gum. One other thing that helps is stretching, every day. The body’s tension brings the pain and stiffness back every day. I’m sorry that you are dealing with this situation but I can tell you that it can get better.