UI suggestion:

The Call and Hang up button are essentially in the same spot and a few times at the end of a call, the doc hangs up before me and I almost click the call button. I've noticed that the docs number is still sometimes there so I am worried that I will call the doc back after hanging up. Not a huge problem because I haven't missclicked yet, but if the buttons were offset - maybe the call on the left and the hang up on the right - I wouldn't run into that.

Maybe set the button location of call and hang up side by side versus the same position overlay (Similar to how an incoming call has answer ignore side by side)