Yes I actually feel like this 90% of the time. I know the feelings are caused by my anxiety, but at the time I feel like it’s really hard to tell if it is a “real” sick feeling or not. I seem to always struggle between knowing if it’s real or not. Also the winter months always seem the worst. One I think it because everyone is sick which makes me think I could catch something. Two because when it’s cold I start to shiver a lot which seems like it brings on the anxiety. If I were you I would go to a doctor and tell them your symptoms. They can do many tests and it might make you feel better knowing nothing is wrong or if there is something wrong you will know what it is and can figure out the treatment.