1) Don't use the cleanser they gave you at the piercing place. It's awful for piercings. Use a sea salt soak (google that phrase and instructions should pop up for how to make and use one).
2) If it's not 316LVM stainless steel (what's marketed as "surgical stainless steel" is actually a variety of grades with a variety of impurity levels), 18-24 karat gold or titanium jewelry, she could be having an allergic reaction to the metal. I had one when I was little - it started out as a little redness, eventually my ears swelled up over the earrings and they had to be surgically removed. Most likely this isn't the issue, but really watch out for any sort of swelling.
3) In the future don't use a place that uses a piercing gun. It does all sorts of nasty damage to the piercing site and makes healing more difficult -
http://wiki.bmezine.com/index.php/Piercing_Gun for more info