Infected nipples??

Hey all

So I got my nipples pierced early October and have kept up with the proper cleaning like my piercer suggested, I did go swimming just after the 6th week (my piercer said to wait 6 weeks) but I made sure to clean it straight after, I’ve been trying to avoid putting pressure on them but when I’m asleep I tend to roll onto my stomach, the issue I have is one of them is healing fine with no issue the other is sore, swollen and looks like it’s started to migrate a bit, I’m just not sure why or how? What could I do to help it heal???