skyla iud?

so i’ve had skyla for around 2 years now and my periods are so light, only spot with brown blood, and i get tender boobs a week before and slight cramps. my period is in 2 days and my boobs were only tender a week before but suddenly arent, and i’ve only cramped for 2 days ish. when i wipe there is a slight tinge of brown but you can barely see it, and i’ve felt for my iud strings but i can’t feel them (it’s happened before) but it is causing worry to me a lot. what should i do? is pregnancy a possibility? i’m SCARED