Sensation in the lower back

Hello everyone! I seem to have an odd symptom but I’m not sure where it stems from. After a long haul flight last November, I have had anxiety, just like in the chest/stomach, but at the bottom of the spine just above the tailbone. I do experience some pain with this from time to time but I don’t know if that’s related. When the anxiety wave happens it shoots down my legs, and then I of course get the anxiety elsewhere. It happens when I have been sitting, but not every time I sit. Just wondering if anyone has anything like this.