What are the manifestations of discontent with Allah's decree? Is feeling sad, distressed, and reaching the highest levels of anguish considered discontent? How do I know that I am patient and not discontent, especially since I strive to say "Alhamdulillah" during those moments?

Among the manifestations of dissatisfaction with divine decree are discontent with the divine judgment and abhorrence of tribulation. Contentment does not necessitate contentment with what has been decreed; rather, it is legislated for the servant to strive to remove what has afflicted him, such as seeking treatment for illness and earning a living for poverty. Be diligent in [reciting] remembrances [adhkar], supplications for distress, associating with righteous women, and perusing books of spiritual edification and biographies of the Salaf.