[Serenity85]

Typical maybe but it does make sense for everything. First Nanoha got careless and over did it and she nearly paid for it greatly. Up to this point S1 --> S2 she was nearly invincabley this incident was a big slap in the face to say "your still human" Tea was reckless (maybe not in the same way as Nanoha) but she almost cost her best friends health/live. Same deal in the mock battle. She was going way to hard and using skills she hadn't mastered yet and she could have gotten really hurt if it was for real and not a mock fight.

Everything be it slightly different, in the end the results could have been the same, so Nanoha was in the right for the punishment be it harsh or not.