i went on a week diet, yet my body still looks the same. what did i do wrong?

Answer 1

You expected immediate results when it actually takes months to see results from a diet. 

Answer 2

Physical changes in your body by dieting takes longer than a week

Answer 3

Did you exercise too?

A week typically isn't long enough to see changes though

Answer 4

Changing your eating habits does not produce immediate results physically.  Slowly slowly is the key.