Spotting or Period? 😵

So, this is going to be my first cycle with an IUD. I have been experiencing random moments or days of cramping and spotting (ranging from very light to alarmingly heavy), which was what I've expected per the prior research I did. However, as I get nearer to my anticipated period start date I am beginning to wonder at what point I should consider it to be spotting vs. menstration? In the past, I have been fairly consistent and regular with my cycle, but I read that hormonal IUDs can make it become irregular. Just wondering what I should expect in the coming days. Thanks, y'all!