Broody already??

[abecca]

I think my chicken is going broody. She has spent the past two days in the nesting box and is making funny noises and getting defensive when I touch her. The weird thing is... she JUST laid her first egg a few days ago. She's only 25 weeks old. What's wrong with her? Should I get some fertile eggs for her to lay on?

Also, is it dangerous for her to hatch chicks in the fall?

 

[Peplers chicks]

I you are sure about the broody, absolutely, why waste three weeks on one egg