Help!!

So I’ve been on the IUD birth control for a little over a year since my son has been born with no periods and just recently (past 3 months or so) I’ve started getting irregular periods. Sometimes it’s just spotting sometimes it’s a heavy period that lasts over 7 says. Also just recently, I’ve started having spotting (when I’m not on my period) during or after sex with the hubby. The sex isn’t uncomfortable and doesn’t hurt but when we turn the lights on in the morning it’s like WTF! Has this happened to anyone else with the IUD? We have four kids and I refuse to use depo (conceived my youngest son on depo) ! I go to the dr October 19. Please help