Paragard and weird discharge?

I got my paragard inserted September 21st and got my period the next day on my usual cycle. Now my next period is due in 4-5 days but for the past week or so I've been having moderate to severe cramping that lasts anywhere from 30 seconds to two hours. I thought it might just be my body adjusting to the IUD but yesterday I noticed pale yellow discharge with no odour and today the discharge was light brown. Have not had sex since insertion due to bf being away at school. Is this just my body getting ready for AF or something I should call my obgyn about? I have my checkup appointment scheduled for the 25th of this month.

UPDATE 10/15: my period started today 4 days early so i'm no longer worried!