shamefaced in WordNet English dictionary

1. showing a sense of guilt
   "a guilty look"; "the hangdog and shamefaced air of the retreating enemy"- Eric Linklater
   guilty  hangdog  shamefaced  shamed 
   
2. extremely modest or shy
   "cheerfully bearing reproaches but shamefaced at praise"- H.O.Taylor
   shamefaced 
   
3. showing a sense of shame
   shamefaced  sheepish