changed behavior

my 2 nd half year baby girl behavior has changed drastically these days.It seems that she is diong everything knowinly.she just does the opposite whatever we say no matter how many times we repeat she just doesn't want to understand.she has become bit wild too,started beating us and other kids.unexpectedly bites and not at all afraid of our scolding and slaps.sometimes she throws expensive crockery knowingly and always want to go outside for a walk or by car.not at all interested in watching T.V or playing by toys.she just want to be with us and trouble us.whenever I get angry she runs to papa and whenever my hubby gets angry then she comes to me but she'll not listen to us.generally in the evening when I am tired she becomes aggressive and do such things.plz help what should I do as I am very upset due to this change.

[babygirl6152]

it's possible she is learning she can have this much power over others.....

what consequences does she receive if she does not obey?

What does she do that is sweet?
How many times has she bitten someone?
How many times has she broken things seemingly on purpose?