I woke up from surgery with labour pains

At the beginning of december I went in for surgery to get the Merina inserted. I'm 15 and I suffer from extreme period cramps so my gyno told me to get the merina. But when i woke up from surgery I was screaming and I was told I was having contractions. I then had to stay the night in hospital and was bed ridden for the following 2 weeks. It's almost been a month now and it's still hurting. Is that normal????