I don't agree with Mirena and its long list of side effects, but frankly it seems like you're looking for something to blame. Your problem has a common onset in women over 35. Low vitamin D levels for prolonged periods of time (caused by not getting sunlight, not by birth control) has a strong correlation with autoimmune disease and inflammatory symptoms such as yours. You should look into that rather than blaming Mirena. Perhaps you should also look into inflammation studies, there's evidence that diet plays a big role as well. People claim to better manage autoimmune and inflammation by getting their ratio of omega 6 to omega 3 down to 4:1 or even 2:1, whereas normal diets high in fast food and oils leave most with a highly unbalanced ratio of about 20:1. It just doesn't seem like Mirena is the culprit on this one. Some people just develop diseases, inflammation, etc.