Mine does the same. Your car is set up to unlock the driver's door only on the first click of the remote. If you've got a highline display, you can change this yourself in the settings. It's designed to make it harder for someone on their own to be hijacked when they returns to their car.
The boot unlock on the remote only works if the rest of the doors are locked. Once you've opened and closed the boot again, it automatically locks itself.