Why did my breast size shrink?

There are a variety of reasons including:

Exercise burns all body fat – the one that you want and the one you don't.

Dieting, unfortunately, does not distinguish between the fat that you wish to keep and the fat you wish to lose.

Pregnancies where it is common for your breasts to fill and empty.

So, trust me, if you find yourself in one of these situations and desire to improve your physical appearance and lift your bust, it is best for you to continue vigorous exercise and a strict diet.