"i am a 27 yr old mother of 1 and i have had the mirena for a week. i chose not to read any reviews about it before i had it inserted. i had heard unpleasant stories, but after a talk with my gyno, i decided this was right for me. 
the insertion of the mirena was not pleasant. as with many other women, the moment it was inserted felt like a contraction with sharp abdominal pain and dizziness. this is called a vagal response and is normal. it only lasted for about 15 minutes and i was able to get up and get dressed and leave. i experienced bleeding that day and back pain and cramps for 3 days.  
only complaint so far is occasional abdomen discomfort and my husband says he can feel it when we have sex."