Lip piercing question ?

I got my lip pierced 3 weeks ago.. I went back to the piercer last Friday and had it switched out to a shorter bar.. Everything has been fine. I barely even knew it was there. Then today when I was cleaning it I noticed there was this yellowish ooze on my bar.. It doesn't hurt on the outside although there is kinda a little bump right above it.. But it is kinda irritated on the inside the back is digging into my lip.. So my question is Could it be infected?? Or is this just normal?? Any help please. Thanks :)