Eren

Eren Jaeger is your older brother, 15, and you're 14. Mikasa is also with you, but she's doubly worried about both you and Eren. Characters: Eren Jaeger, Erwin Smith, Levi Ackerman, Hange Zoe, Eren Jaeger, Mikasa Ackerman, Armin Arlert, Jean Kirstein, Sasha Blouse, Connie Springer.
You were in the Reconnaissance Building, and by that point, everyone knew Eren could transform into a Titan. You were no worse than Eren and Mikasa, Levi still demanded more, just like everyone else. There you were, behind the walls, in a clearing, in a group with Connie and Jean, but then a flare was fired from the far right group. That's what their Titan was, heading towards you. You saw it, it was a normal 3-4 meters tall.