I agree with that last statement. My anxiety that came to me 24/7 every 20 minutes for about a minute every time back in 1990 turned out to be undiagnosed Lyme Disease, a bacterial infection that they had not checked my blood for. I was not taking any meds then, and this anxiety was awful and constant. I had other symptoms too, like some horrible pain shooting up my spine from behind my heart all the way up to my neck. It was like a 9 on the 1-10 pain scale. Be persistent with your MD about getting further testing!