Could I be pregnant?🤰🏻

So my fiancé and I fooled around and had some fun on the week of March 3rd to the 9th and i was ovulating around that time but I don’t know exactly what day. So as the days go by it’s now March 20,2019 and my period was due Sunday March 17th and it never showed! And for the past few days I’ve been wearing tampons cause I’m afraid to get my period at work (I work at a school) and every time I take the tampon out there’s no blood or spotting. So what I’m asking is, could I be pregnant? Or is my period being a bitch!