Mirena, yes or no?

My OB suggested Mirena to me at my 6 week check up after the birth of my second child. It sounded great. After reading your postings I am beginning to wonder if I should even attempt this.
I used Nuvaring after my 1st birth and had side effects that caused me to give it up. The 3 weeks on I was agitated, grouchy and constantly tense among other things. When I removed it for 1 week I always felt like a weight had been lifted. I do not have a history of Depression or anything like that, but I do suffer from PMS anxiety. I had side effects when I took the pill several years ago. I am currently taking a pill (only 1 pack so far) that has not had any side effects yet.
I am just looking for honest opinions from women that have used mirena. Thanks