I'm so scared that my nipple is dying, is this color normal? Normally my nipple color is very pink. (Photos)

Based on your pictures you seem to be healing well, bruising is normal and will continue to be for a few months just give it time and continue to follow up with your PS.

It is hard to judge from photos and if you are concerned, you should see your plastic surgeon. But from what I can see on your photos, the areolae appear to be bruised and the perfusion to the nipples appears to be fine. The bruising can take up to fours weeks or longer to settle completely before you see your pre op nipple colour. 

It would be very helpful if you did mention how long has your surgery been done, because bruising and swelling are normal manifestation of healing in the early stages of recovery. Having said this, it would be difficult to give an accurate assessment based on photos. Your best course of action would be to schedule an appointment with your board certified plastic surgeon as he/she knows your condition best.