What happened to my period?

Hi everyone,

My period with Mirena has been fluctuating, I had it inserted Dec 2016 and have had regular periods up until September 2017, when I started having 2 periods a month. I went on addition bc pills to regulate my period and have stopped taking them after February because I skipped my period that month for a trip. It's March now and I haven't had a period yet. Should I be concerned? I've also been stressing out a lot so I don't know if that delayed my period more. Opinions?