As long as the jewelry you bought is implant quality...ie, 316 steel or titanium...you should be ok to change it in 4 to 6 weeks, depending on your healing progress. If you are experiencing any problems you should wait longer. If you bought "cheap" jewelry, you need to wait at least double that. Getting the screws in can be a bit tricky if you haven't done it before, so make sure you aren't tearing you nose up attempting it. If you can't get it, don't keep trying...you will just traumatize the fresh wound. Your piercer should have explained this to you. Also, depending on placement of the ring, there is no guarantee that it will fit right out of the case, and you may need to be fitted. Stay away from the nose bones until VERY healed, and even then, I think they are a poor choice.