Is this supposed to happen

I got Miranda 2 months after giving birth, and the following week I got my period back. I had about a month of spotting, then it stoped and periods went on normally for 2 months. Now I’m getting cramping and bleeding but it’s not time for my period and it’s heavier (normally I barely even notice my period). It’s been going on for 3 days. Does this warrant a dr visit or just one of the things that comes along with iuds? I’ve heard they make your periods lighter but I don’t know if they make them irregular?