Hi there I'm 17 my breast are growing down along with my nipples, what do i do?

It sounds like you are describing ptosis (sagging of the breasts). Without photos it is impossible to give you an opinion. I recommend consulting with a board certified plastic surgeon to discuss your concerns. Best of luck.

It is normal for nipples to grow with breast development.  However, without photos or more description of what you have, I cannot give any advice except to meet with a plastic surgeon and discuss your options.

It sounds like you are describing ptosis (sagging), but it's hard to properly assess the problem expressed in 10 words or less without a photo at least. Even with a photo, best bet is a consultation with a plastic surgeon in your city. Good luck.