I'm not sure I can help but I do know that you can simply think about a symptom and then start to feel it. That happens to me many times when I'm Googling something and I start to read the symptoms. Suddenly, I'll start to feel those symptoms that I did not have before.
Or I'll just think about it and it will start. My father was in the hospital overnight last week due to chest pains. It turns out he was fine. However, that same night, I was worried about him and starting to feel chest pains myself. Just thinking about it along with the worry and anxiety started those feelings.
I wish I could be more help. Our minds are very powerful. I hope you feel better.