So I'm pretty sure someone stole my phone last night and I keep refreshing find my iPhone as much as I can but to no avail. What can I do to get it back?
Did you have find my phone active before? If yes, then it should be displayed. If not then it might be turned off. As long as you have find my phone active your iPhone cannot be restored to default settings.
Are you sure you had Find My iPhone turned on? I would call the police. Was your phone on when you last saw it?
Retrieving data ...