sheepishly

/ˈʃipɪʃli/
adverb
  1. In a way that shows embarrassment or shame, especially after doing something silly or wrong.
    • The dog wagged its tail sheepishly after being caught stealing food from the table.
    • He sheepishly admitted that he had broken the window.
    • She smiled sheepishly when her friends caught her singing in the mirror.