No offense but I doubt you don't actually have infrmammary folds. You may not have much breast tissue but pressing down on what you have may help to define it. Your likely best option, although a picture would definitely help, is a breast augmentation to enhance the proportion of...
In all likel;ihood you are probably not allergic to the implants but perhaps a medication your surgeon put you on such as a pain med.I would call his office.
I would bet that in surgery, while you were asleep or sedated, that when your surgeon sat you up the implants look well positioned.
The breast implants, and placed under the pectoralis muscle sit in a pocket much in the same way that an item dropped in the bottom of a long envelope would sit...