Task: Identify the primary emotion conveyed in the tweet and assign it to either 'neutral or no emotion' or one or more of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust) that best capture the tweeter's mental state.
Tweet: @SkyUK I was just put on hold for 20 minutes till I hung up. #not happy #terribleservice #unhappy @virginmedia I should have stayed...
This tweet contains emotions: 
anger, disgust, sadness