Silent Turns Deadly

What happened?

Yamato, Leo, Tusk and Amu went grocery shopping without Sera because she refused to. Sera has been acting strangely for the past few days and only Yamato noticed.

Before everyone left to go shopping
"Sera, would you like to come with us to shop around?" Yamato asked.
"No thank you." Sera said in a serious tone.
Yamato notices Sera hasn't been acting like herself but rather in a serious mysterious mood.
"Are you ok?" Yamato asked worryingly.
"I'm fine, you don't have to worry about me." Sera said in her serious tone.
Sera then left to go to the kitchen mostly to avoid talking to Yamato again.
"Yamato, why are you taking so long?" Leo asked standing at the opened door.
"Nothing I was just asking Sera if she wanted to go but she wants to stay here." Yamato replied in a sad tone.
"Let's go guys!" Amu whining because of the long wait.
Yamato and the rest except for Sera (of course) were having fun going to new shops. But Yamato was extremely worried for Sera but decided everything is fine.
Meanwhile Sera was sitting on the couch, there were tears rolling down her face.
"Why does this have to happen to me?" Sera thought.
She decided to leave the treehouse and go on a walk to clear her mind.

Yamato and the others came back from the long shopping spree and the first thing Yamato notices is that Sera wasn't there.
"Where did Sera go?" Yamato asked the others in a worried tone.
"Maybe she wanted to go on a walk and hasn't came back yet." Tusk suggested.
"Why are you so worried Yamato-kun" Amu questioned.
"No it's just Sera has been acting very strange the past few days." Yamato explained.
Sera was trying to find her way home but got lost, she was about to call Yamato on the champion symbol but remembered she can't, so she just put the champion symbol back where it was and continued her search.

I HOPE YOU GUYS LIKED IT!
I'LL BE UPDATING VERY SOON (PROBABLY TOMORROW BECAUSE I HAVE NOTHING TO DO!)