What is the reason for my feeling of distress, worry, intrusive thoughts, anxiety, and depression after repentance and righteousness, while I did not feel that way during the period of sins and transgressions?

The questioner was advised to increase gratitude to Allah for the blessings of repentance and recovery from illnesses and whispers (waswas), and emphasized the importance of supplication and humility to Allah for the rectification of the heart, tasting the sweetness of faith, and perseverance in acts of obedience and striving in them while maintaining good thoughts of Allah. It was noted that Satan seeks to cause sadness and turn a Muslim away from righteousness, and it was urged to seek refuge with Allah from Satan, disregard his whispers, and continue to do good deeds, repent, and seek forgiveness.