Random spotting after a year??

I got the nexplanon inserted almost exactly a year ago. I got my period not long after, and honestly for the most part they’ve gone away, minus one randomly about six months ago. The past few days I’ve noticed quite light spotting/brown discharge similar to what I’d get before my period started/as it was ending. I’ve not had any during this year! I know irregular bleeding can be a common side effect, but is it so normal after this long? Or did anyone else suddenly get new random side effects after a while.