I can't tell what's my period and what's spotting after iud

I got an IUD (Mirena) over a month ago (June 7th) and since then I've had very frequent spotting. It will happen at random and often it's varying shades of red. Sometimes bright, but often dark almost brown. It's a little confusing because now I can't tell what's considered my period and what's considered spotting. Sometimes it's very heavy and sticky and other times its light and it wont show up on my pad but it will when I wipe. I'm not sure how to log it anymore so I've just been logging it as spotting and when it was time for my period I logged the bright red as my period and then spotting when it went back to dark. I'm not sure what it's considered now. Hopefully it stops soon because I really don't like having to wear pads every single day.