Thanks for posting your query in Health Care Magic , and i understand your concern.
The ideal weight for your height is 110-130 pounds, you weight 10 pounds more and i do not understand why you are taking diet pills as i can see you are not extremely obese
The extra 10-13 pounds which you have gained can be lost by moderate exercise and diet. You may have tried dieting and exercises all and would have given before you even saw some results. Every diet or routine exercise takes at the least 3-5 months to show some effects on your present weight .
I suggest you to start the balanced diet and exercise all over again , and to do it for atleast 4-6 months , do not get disheartened if results dont show up in the first one-two months. And losing weight has nothing to do with your age.
Once you reduce weight , even your breasts size will come down and sometimes bigger breasts are genetic and cannot do anything about it.
Just ear right, exercise well and stay healthy.
Hope this helps and answers your query.
So get the diet started , keep a goal and work towards it. Losing 1 pound a week is healthy.
Good luck and wish you good health.