Painless IUD?

I got the Mirena IUD inserted a few days ago. During the procedure I literally did not feel a thing considering they did numb my cervix with a spray. Even after I had the slightest cramps but not even as bad as a normal period for me. Is this normal? I feel like I've only heard stories of people having pretty bad cramps after. Could something be wrong or am I just one of the lucky ones?