Define How I'm Feeling Meaning

How I'm feeling, sometimes you don't know how you are feeling but you feel sad, but nothing is causing it and you have a decent life, you like being sad bc it's all you can do. That is how I'm feeling

The fifth line of the song 'Never Gonna Give You Up' by Rick Astley, or the first line of the pre-chorus.
Spoken only by men of wisdom.