Iud cramping

I am having terrible cramps right now... I have had my iud for 2/3 months (skyla) and have been having unprotected sex since I got it. I usually get bad cramps before I'm about to start my period but I have only had 1 period on skyla cuz my periods are irregular. And the one period I got was terrible I had the worst cramps ever like I had to lay in bed cuz I was in pain. Is this just a period cramp? If so will they get better? Or could I be pregnant and this is a sign? Please help I'm very paranoid