It is very common to have nipple swelling when you have a nipple incision. I would give it a full 3 months to heal to allow swelling to subside and the implants to settle further. You should address your concerns with your plastic surgeon.
While anything is possible it is VERY unlikely to occur. I would be more concerned with the other more usual complications. In over 10 years of breast implant placement I do not think I have ever seen permanent loss of nipple sensation. Good Luck!