YES..... having one breast bigger than the other is normal, heck some people that pay 5,000 to 10,000 for breast implants and still end of with this issue due to tissue capsulation.....
My suggestion to you would be to bring the matter up with your doctor - as to calm your inner fears - and then if the complete cup size is still leaving you feeling self conscious or out of place when around other people, then by all means look into some cosmetic surgery - many people have surgery to correct the very issue you are concerned about.
LoVe,
Rhapsody - (((

)))