I totally sympathize with you! I am on my 15th week post removal, and I'm not sure if it's my impending cycle or what, but I am feeling like crap. I finally caved to my Naturopath who specializes in hormone balance, and started using the progesterone cream to jumpstart this cycle. I was having a horrible "crawly" feeling all the time, possibly anxiety, and would wake up in the middle of the night with awful night sweats and my heart pounding, unable to sleep. The Progesterone cream has helped with sleep issues and anxiety, but I really REALLY don't want to use it again after this cycle. I am understandably leery of any kind of hormone manipulation at this point.
Please let me know how you are doing with your heartburn as time goes on. This has been my strangest and definitely the WORST of my post-mirena symptoms. I also have horrible reflux now, which I never have had in my life, and I'm hoping it settles down once my hormones are in balance. Because of other stomach issues (also due to Mirena -- ARRGH!) It's not a good idea for me to use antacids or PPIs. So I'm doing my best to deal with it naturally.
I'd love to hear how you are doing with all your symptoms as well. Hang in there!