hi, sorry to hear about all your difficulties...i didn't develop the bad back pains and cramps you describe but did develop a sore back for sure. the numbness and tingling and lightheadedness all developed about 6 months after having my mirena in. i've had 2 normal MRIs of my neck and head, and just today had my mirena out...hopefully that was the cause of my strange symptoms...i'll keep you posted! hope you feel better!