A piercist will always properly sterilize their equipment and the body jewellery, this is to reduce the risk of infection. When piercing at home you are not likely to have all the correct materials that have been cleaned.

A professional piercist will also be able to advise you on proper cleaning techniques and healing times. Without this knowledge you could end up with a nasty infection or worse. On rare occasions an at home piercing, done with out any supervision can get so badly infected it can be fatal.

So all in all it is really not worth it! Wait till you can go and see a professional piercist who is able to do it properly for you.