Ok, normally I write standard reviews, but I would like to make this one also aimed at @psy0000.
I agree with him on the first point, you didn't tell us why the Robot was angry. Although most will generally accept the cliche "the robot goes evil" it is still a cliche, and it detracts from any form of characterization.
I actually liked the Trololo music. Well, I liked it juxtaposed to the dubstep. Beside each other it created a real difference between the toy and the monster. Showing change. Although, without a reason why the robot was angry it wasn't as powerful as it could have been.
Who cares about weather or not the robot could hear the screams. The screams were to add texture and power to the robot and his destruction. People were being attacked in those buildings, suffering and dying. It showed the viewer that there were real conciseness to the robots actions. I quite liked the screaming.
He is right that we have no reason as to why the robot was mad. But the ending was a little ominous. The only problem was, the robot only had power when it was big, so why should we fear it as a toy. Lighting never strikes the same place twice.
It doesn't matter that the boy was unharmed. This isn't some ultrarealistic movie. This is a cartoon. One doesn't need to follow the laws of physics. A toy robot was turned huge by lighting and attacked a city, and then was struck by lighting again which made it shrink. If someone's problems with that cartoon are that the robot wouldn't be able to hear the screaming and that the boy should have been harmed. That person is an idiot.
It was not bad. If it was supposed to be bad, than you failed at making it bad. I say good job. Maybe next time add some audio (other than SFX and screams) and maybe some character development.