LOL i'm not a Bayer employee, but i do live in canada, maybe we get better info with our drugs here then because I did get a whole booklet with my product explaining all the side effects and the Mirena.ca website states this about the side effects:
Apart from menstrual changes, other side effects might include lower abdominal pain, headache, Acne or other skin problems, tender breasts, backache, a feeling of sickness, or period pain.

The following side effects generally do not require medical attention, and will disappear as your body adjusts to MIRENA®.
Common: changes in bleeding, nausea, acne, breast pain or swelling and weight gain.
Uncommon: hair loss or excessive body hair and decreased sexual desire.

If you think you are reacting poorly to MIRENA® or are having other problems, please tell your doctor.

My booklet also listed joint pain, abdominal pain/cramps and ovarian cysts aswell as PID uterine perforation or embeddment which could lead to infertility. I appologize for critisizing if you didn't get this info with your product (it's in the box it comes in) or maybe your doctors didn't give the booklets to you :(