How To Reduce Heavy Breasts?

Hi. Im female, 5 foot 4 (just) and 22 years of age. Im 14st 11, and have recently lost a stone in weight over a period of 12 weeks. I have a large chest size, and after losing a stone i thought my size would reduce but they just seem to get bigger. I have pains in my neck, and in my chest if i don't wear a bra. They are really heavy and are making me unhappy. What else can i do to stop the growing?