Hi nile.
I've not posted on this forum before, but I too have had a variety of adverse effects that I believe are caused by mirena. Your recent post intrigued me, because your symptoms sound similar to a condition from which a friend of mine suffers, known as POTS. This can occur as a result of pregnancy or as a reaction to a bad drug (hers was brought on by adverse reaction to Yaz) and causes extreme blood pressure swings, dizziness or fainting, heart rate variations particularly when they are not appropriate, and can occur with adrenal symptoms. The definitive test for this syndrome is a tilt-table test, which could be done during pregnancy (it is simply an EKG performed in different positions), though the results may not be considered accurate because of the pregnancy (apparently this condition can occur then disappear because of pregnancy). Unfortunately, it is not an easy condition to treat, and many doctors are not well informed about it. Best wishes on the rest of your pregnancy- your body has taken care of you this far, and I'm sure it will carry you through.