Strange experience this morning trying to open driver's door

My 2017 Prius Prime is normally left unlocked in my attached garage.
This morning when I tried to open the driver's side door, the latch assembly only opened part way. I had to pull on the handle again for the door to release fully and open.
I tried to open it again a few times. Each attempt required pulling on the handle twice for the latch to release completely and allow me to open the door.
I then noticed that when i held the handle, instead of silence or the two beeps to signal unlock, there was a muffled clicking sound for as long as I held the handle.
This has never happened to me before.
I took my smart key into the house and tried opening the driver's door with my wife's fob and everything worked properly.
I replaced the battery in my fob and everything seems to be back to normal.
I don't really understand what happened, since the door was most probably unlocked to start with.
But, my experience with this vehicle over the years is that every time I think something isn't right, it turns out to be user error (on my part). So...
I know that most of us are familiar with the smart key system and how it operates. Even with a dead fob battery you can open the door with the metal key and touch the dead fob to the start button to be on your way.
This behavior is new and previously unknown to me.