Period came back

So I got my IUD in August of 2024 but starting 3 days ago, I got my period back. I stopping getting my period in October of 2024. I took plan B last weekend so I assumed that the spotting came from that, but now I am full on bleeding and it seems to be a period. Is this normal? I have been under a lot of stress recently because I have an upcoming surgery and I have been cramping here and there but that’s about it. Did my IUD move out of place, am I pregnant, is it the plan B, or is this normal and I’m just getting my period again?