iud/period trouble

hello!

i’m kind of freaking out. i have a skyla implant, and i usually have my periods frequently, about twice a month. but i haven’t had my period at all for december. i’ve done “the dirty” more this month than usual too. but i’ve never had a pregnancy scare or a late period or even skipped a period. i know my skyla needs to be replaced soon, but i’ve never kept track. (i know it was around march of 2017)

ive been trying to feel for my strings, and i can’t feel them at all. but after every time i try, i start cramping pretty badly. i may be over exaggerating, but i just need some advice! maybe similar stories! anything will help :)