Belly on piercing was infected..?

I thought my belly piercing was infected so i called my sister who had one and she said whenever she got a small infection she used iodine on it.. I thought she put it on and let it sit but she used it in the shower then washed it of. I let mines sit. The piercing went down but im still going to the place that pierced it to see what i should do because i wanna take it out, but the iodine got in my belly on(so i took a shower and washed it all off) and now the area around my belly is swollen... NOT my piercing. So basically my question is, is it normal for iodine to cause swelling and when will it go away. Plus it's not A lot but it's still scaring me.