shamefaced (adj.)

• abashed
• ashamed
• bashful
• blushing
• chagrined
• chapfallen
• confused
• conscience-smitten
• conscious
• coy
• crestfallen
• crushed
• demure
• diffident
• discomfited
• embarrassed
• hangdog
• humbled
• humiliated
• inarticulate
• meek
• modest
• mortified
• mousy
• red-faced
• regretful
• remorseful
• rueful
• self-conscious
• self-effacing
• shamed
• shameful
• sheepish
• shy
• skittish
• sorry
• timid
• timorous
• uncomfortable
• wistful