mirena & tampons?

Sooo I'm super new to this & have never posted before but I just had the Mirena inserted today (seriously worst pain I've ever felt!!) but anyway, my dr didn't give me much instruction and I was wondering if it was okay to use tampons tomorrow? Today was the last day of my period, but due to the insertion I am still bleeding just a small amount and I truly hate wearing pads, especially at school. Also... for any of you that have/had mirena.. how long did your cramping last!? I've been in pain ever since! 😞  thank you all in advance!! 😊