Does feeling remorse over a satanic whisper that took hold of the heart, leading to loving a young man more than Allah, despite praying for steadfastness, necessitate anything?

There is nothing upon you from what you mentioned, and you must continue to resist these intrusive thoughts until Allah completely removes them. They will not harm you as long as you dislike them and are repelled by them, and you will be rewarded for struggling against them. As for your love for the young man, you must strive to free yourself from it.