Sorry for your loss, always terrible when they sneak out on us. A shame you didn’t had more time together. Don’t let this encourage you from this beautiful hobby.
When did she show for the first time restless behavior? My first guess is she is in her receptive phase at the moment and is still developing eggs. The second restless period is mostly the one she's looking for place to lay her eggs.
Agree with @LizardLurkin and wanted to ask the same. And...