Ear stretcher help

I recently went from a 10mm to 12mm in one ear and noticed after it was healing, it started leaking pus (just from one part). Its been two days since I noticed that. The material is a metal tunnel, from a certified piercing shop. It kinda stopped leaking tonight and I wiped it with a tissue, and decided to use sea salt and warm water to rinse it. I'm not sure if it's just cause it's irritated, or having a bad reaction but it feels kinda scratchy now. What is a safe reaction to feel after rinsing a piercing with sea salt? It's possibly fucked now.