Why does my Monroe Piercing have a small lump in it? & it's accompanied w/ pain.?

I've had my Monroe piercing since February of this year. All of a sudden it has started to hurt & I feel a small ball that has formed inside my lip. There is no swelling or leakage at all. (no pus or blood) It just hurts and it feels like something has formed iniside it. Is there something wrong? I took my barbel out so it wouldn't hurt as bad, but once I went back to put it in yesterday on the inside of my lip it had closed. So I took my barbel and put it in through the top (front) of my lip and found the hole. Should I take it out for good? Or is there anything I can do? Because it's hella painful....