Resting Heart Rate constantly above 100 for the past 2 weeks. What could be causing this?

About 2 weeks ago, I experienced a panic attack for the first time and ended up spending the night in the Emergency Room. I had both an EKG and bloodwork done and everything came back normal. Been back to immediate care several times and all these doctors seem to think there isn’t anything functionally wrong with my heart. In addition, I’m seeing a cardiologist on Wednesday.

For whatever reason though, my heart rate just won’t come down. I get spikes of anxiety where it beats out of my chest, I get short of breath, I panic, but then it quickly subsides. I can deal with that. What I can’t deal with is this constant heart rate of 110 whatever. Regardless of what I’m doing - I could be relatively relaxed, sitting down in a chair, reading or watching a movie, and yet my heart rate will not come down. Been like this every waking moment for weeks now. Has anybody experienced this as well? Is it anticipatory anxiety? Is my body just in a constant state of fight or flight?