Mirena and organisms

I am 34 years old. I went to the OB today after having Mirena inserted in August. I had a baby last March and was nursing her at the time. I had asked my OB a few months ago if fatigue was a side effect, as I have been just exhausted for months. She said no. I am exercising, eating exceptionally well, and losing very little weight. I have been extremely emotional--on the verge of tears all the time. My marriage is terrible right now.

I mentioned at today's appt that I had some irritation/itching/rawness feeling in my vaginal area. She did a culture of my discharge and said there was no bacteria/infection, but she saw some "premature" cells, (I don't know recall exactly what she said, is a blur, but she gave me estradiol vaginal insert tablets and told me to use them for 3 months. She said that maybe starting me on Mirena while I was nursing got my estrogen too low and that I "shouldn't have to be on this {estradiol} forever." Am I now experiencing premature menopause? No wonder I've suddenly sprouted gray hairs over the last 6 months!