Belly Button Infection?

I came home and changed out of my work clothes and I didn’t notice until then that I had some sort or scrape/cut in my belly button?? Before I had cleaned it, it had crust and a little bit of puss like substance. I don’t ever remember getting hurt and I didn’t even feel it so I’m not sure how long it’s been there. Can someone help me figure out what this is and if it can be dangerous?