have you ever got angry while watching clannad?

Not at all, because Nagisa is always there, and that makes it happy, not sad.^^

Ehh.. I have a few times.

Like:
~When Youhei was being an asshole ignoring the little girl who was being picked on. (And acting like he didn't care about Mei)

~Tomoya letting Ushio persuade him to go on a trip w/ her when she was very sick. (Leading to her death. *sorry, spoiler*)

~When the douchebags from the soccer team kicked a ball into Mei's stomach..

~Tomoya acting like a douche to Ushio when he met her after five years..

^ All those were from the second season.

In season 1 (EP15), Sugisaka the girl who force Nagisa to give up on establishing theatre club by threatening her.

In season 2 (EP04), When the douchebags from the soccer team kicked a ball into Mei's stomach. EP08 Sasaki's gang don't listen to Yukine's explain and Sasaki punched Yukine.

Only when Kyou and Tomoya were trapped in the storage room together and when Sunohara was being a stupid son of a gun which led to Mei, Tomoya, and Nagisa being pushed around by the soccer team.

the onlly time i got mad waching this is at the end when he ended up with that other girl and not nagsa