What is Betty doing when she falls into Cobb well in the novel, Wolf Hollow?

The old Cobb well, now not much more than a hole in the ground bounded by stone, is where Betty falls in when seeking to make trouble for Toby. Betty becomes trapped in the well after her shoulder is impaled on an old pipe. Annabelle comes to suspect that the well is the only logical place Betty could be based on having heard strange animal sounds passing by on a previous night, and because Andy explained he and Betty sought to cause trouble for Toby, possibly even burning down his smoke shack.