This is what angers me most about this whole thing, that despite the fact that these side effects are listed on the physician information insert, printed by the makers of Mirena, the doctors continue to say it couldn't be the IUD...they're so full of it!!! check out page 13 of this link, it's right there in black and white. Print it up and take it with you to your removal appointment.
As far as the 'crash' is concerned, there's not a whole lot you can do to make it better, but knowing to expect it will help you cope, you'll know your not going crazy. It also helps to have a good support system. Good luck :)