I believe these are phenomenal emotions to experience in meditation, and are half the purpose of it; it is the process of introversion and going within. When we introvert ourselves, we see who we really are, see our negative emotions and memories, see our wickedness and failings, confront our mortality, and see the things about ourselves that repel us or horrify us. But in doing so we begin the process of reconciling those emotions and reaching a more integrated state. This is the emotional sophistication of the great saints and yogis.
Some reading materials on this that are out there are: John of the Cross' Dark Night of the Soul, Jesus and John the Baptist's Metanoia, Evelyn Underhill's Purgation, Alchemy's Nigredo, Carl Jung's Shadow Self, Teresa of Avila's Second Mansion, and more.