Emoticons for Robot - Miffed

My brother is a computer scientist, and as part of one of his assignments he has a robot driving around displaying various facial expressions, similar to GERTY from the movie "Moon" (a good movie, by the way; go watch it).

He asked me to draw some emoticons for him to use. This is the slightly angry 'miffed' one.

):<

Done in Photoshop.