Some of the more fundamental Christian sects frown heavily upon piercings and tattoos. Others, such as the Methodists and their ilk, are likely to be more tolerant.
Depending on your reason it can be justified. I have a septum piercing and 00 ear guages. I believe that these can help me witness to non-christians breaking the belief that you must be in a certain dress code to attend church or call yourself a christian.
There is nothing that says it's wrong to get your nose pierced, but a lot of the older devout Christians look down on things like tattoos and piercings.
The Bible says the body is a Temple of the Holy Spirit. So in my opinion it depends on what you believe. I believe it is ok as long as you do not go overboard like piercings everywhere. Try asking some friends or your Pastor?