mirena help

 I got the mirena in last december so ive had it for about 7 months now. Normally i spot a few days before my period starts and a few days after  but i havent missed a period yet. Ik some women dont get there period on the mirena at all . This month is the first month ive ever been late not even spotting  its only a couple of days but im still alil worried. Could this just be the effects of the mirena or should i take a test?