A bridge too far - Trying to do more than your brain can handle, like trying to

Trying to do more than your brain can handle, like trying to eat a whole cake, run a marathon, and text your crush all at once.

My cousin tried to do 12 tasks in one day. By night 3, he was crying in a cereal box.

My brother tried to learn guitar, piano, and magic tricks all at once. Now he can only play the guitar while crying.

My friend tried to eat 5 burgers, run a mile, and text his crush at the same time. He failed at all of them.