J-Ning's little temper

I am wondering whether have i been spoiling J-Ning too much to allow her to get into real bad temper. Example 1: I m training her to drink from a baby trainer's cup. So she tried, but the next moment, she is toppling the so Non Spill cup upside down n spill water all over the floor n table, so spank her on her hand n u know wat, she slam the cup on the table n also "beating" the table to venge her little anger that i have beaten her. Example 2: We were playing a Lego toy which she has gotten for her birthday presie, she played for a while but later i think she got bored by it n start throwing the toy around. So told her off telling her the toy will be very painful n ask her to "apologise' to the toy. She showed her anger by picking up the toy n threw it to the floor several times n repeated said" beat beat" then slaping the floor ,looking pretty unhappy. Her temper has been getting pretty bad, sometimes i am wondering have i been giving in too much to her that "cultivate" this little anger of hers??