is it normal to develop period symptoms you've never had before ?

so normally PMS for me is light cramping and brown discharge . but for my last couple of menstrual cycles , PMS has been nausea with decreased appetite , fatigue , sore boobs , and a blood hound nose ! i know what you're thinking "wow those are pregnancy symptoms , you should test !" but i've been noticing these symptoms for the past three cycles ! i also haven't had sex in two months and the last time i had sex we used a condom and i'm have the copper IUD ! so i'm 1000% sure i'm not pregnant , but i wonder why i don't get the same PMS as i used to ? ofc when my period comes i get the same symptoms (cramps and back ache) but i still feel a little nauseous until my period gets its heaviest . has this happened to anyone else ?