Based on the given tweet, determine the level of sadness the author is experiencing. Choose from the following options: 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.
Tweet: Boy oh boy! our weekday schedule is crazy! But no matter how tired I am I do whatever it takes to keep the smile on Kai's face from a frown
0: no sadness can be inferred