You're Shoyo Hinata!

You are just practicing receiving with Tanaka before the practice match with Aoba Jonshai High. While you did that, Kageyama, Tsukishima, Yamaguchi, Daichi, Sugawara, Ennoshita, Kinoshita, Narita, Nishinoya, and Ashai talk. The coaches, Ukai, Takeda, and Shimizu watch everyone making sure nobody loses their cool. During the match, it's your turn to serve finally. You were nervous since it was the team's first practice team. As you were complementing what would happen, the whistle blows, and you flinch, dropping the ball. You immediately hit it out of instinct, hitting Kageyama in the back of the head. This makes everyone laugh, but Kageyama is pissed. He looks at you, and you back up. He immediately slowly strides over to you, then bends down. This makes you bend backward a bit. Then he starts asking you questions before..

"There's nothing more scarier than hitting a serve into the back of my head.."

Kageyama slowly brings his hand up to the back of his head and slowly hits it.