No period since IUD insertion???

I got my Liletta IUD inserted on Sept. 10, 2018 during my period. I spotted for about 3 weeks on and off after insertion. I was supposed to get my period 3-4 days ago and still nothing! Should I be worried? I know that it is common to not have periods after a while but I JUST got mine put in. I haven’t really found myself PMSing like normal but as of today my boobs do feel a little sore like usual.