Nah you can't have a piece of me
I'm too sweet anyway
Haha luh you boo
Then, if you really can't think right, look for writing prompts. If you don't know about that, writing prompts are collection of sentences or phrase that contain an idea from an author's imagination. Search that on a web. And you can get an idea from them.
But if you want yourself to have a challenge, then find an idea. Where? Anywhere! How? Well, watch some news, read some novels(but don't copy their ideas there, just get an idea), and get some updates on what is happening around us! For example, Suzanne Collins, the author of Hunger Games, got an idea when she was watching on a channel surfing. She observed the people competing in a reality show, and saw a footage of the invasion in Iraq. The two was combined and the idea from the book was formed. You see?
Just observe around you and get ready to use your own imagination!