Period after 1 1/2 insertion of Mirenea

I got my Mirena inserted Sept 27th, I had light spotting and irregular bleeding throughout the month of October too, there was a point where I bled more because that was the week of my period (I was on the pills before mirena and stopped the day I got it inserted). I stopped bleeding in the beginning of November but I'm supposed to be on my period week right now but no period. I've been having cramps, swollen breasts the regular symptoms. I'm guessing since my body is still new to it I haven't gotten it and it's getting used to it? Help me out girls, give me your experiences.