I have no clue if feeling is a good thing or bad for you. I do have some idea how it originates though.
Attachment –> Expectations —> Ego is satisfied —- (Yes ) —-> Positive Feelings
(No) —-> Negative Feelings
Feelings can lead to daydreaming or over thinking apart from giving depression, anger, insomnia etc. This can result into affecting your present and future. To have a great present you have to live a life free from past prejudice, learnings. A life like an empty slate which is empty and has no affect from outside world.