Visited Duke on Wednesday Night Thursday AM broken down stall door

Got a note from Bonnie that Duke had broken down the door down, took it off the tracks.  This made me very nervous. The night before he was just himself, asking for snacks.  Not especially kicky.  Then I recieved the note from  Bonnie.
The night before we took a walk, had a shower, rinsed his hoofs and relaxed after a hot day.