1) Ill-natured 2) Ill-tempered or annoyed 3) Snorty 1) Snorty 
To get upset or angry.
Shirty is slang for getting angry or upset.
[adj] - (British informal) ill-tempered or annoyed
To get upset or angry
snorty adjective (British informal) ill-tempered or annoyed
Don't get shirty with me young man was what my Dad used to tell me when I was little. He was referring to my response to his telling off for doing some terrible little boy thing. Like tying my brother to the back of Mum's car or putting my shoes in the toilet. It meant I was getting bad tempered.