IUD Insertion

I am sixteen years old, have never had children, and got my first Skyla IUD today. I had some pain when my OBGYN dilated my cervix but there was no pain with actual insertion, just a sense of pressure. Afterward I was completely fine for about an hour. After an hour I got what I assume are bad period cramps (personally I've never had cramp-y periods so it was a new feeling). Now it's 6 hours later and I have light cramping that is diminishing. Unless something changes drastically soon, I think getting Skyla is the best choice of my life so far.