New Track Syndrome
When a musician of any genre (although the term is more often used for hip-hop artists and producers) creates a new song in which they enjoy upon the first couple of listens, but then the next morning they realize that what they had made is absolute garbage. This individual has been a victim of New Track Syndrome.
I made an awesome new song last night but I listened to it again this morning and it seems like it was just new track syndrome or something because the song sucks!