Is a believer's distress and grief over an affliction that befell him considered a sin or an objection to Allah's decree, and can he repent if he tried to prevent Allah's decree after sensing it?

What befalls a servant by way of calamities and sorrows is a mercy from Allah, whether it is a punishment or a test to raise ranks and expiate sins. As stated in the Hadith: "If Allah wishes good for His servant, He hastens the punishment for him in this world." And whatever harm afflicts a Muslim, Allah expiates his sins thereby. There is no sin upon a person for feeling distress and sadness due to calamities, as long as it does not lead him to commit something unlawful, because these are psychological matters he cannot repel. And attempting to avert calamities is not an attempt to prevent destiny, because a person does not know what has been destined for him. Sincere repentance expiates all sins, for "the one who repents from sin is like one who has no sin."