Using the tweet "Today is a 'stay on bed ' day.  So snuggling up with Casey. I couldn't sleep last night.  #panicatracks", determine how much sadness is shown. The categories are: 0: no sadness can be inferred, 1: low amount of sadness can be inferred, 2: moderate amount of sadness can be inferred, 3: high amount of sadness can be inferred.