For the last week I've been experiencing the following symptoms: severe pain in my abdomen and sides to about my hipbones, low grade fever, nausea, very early period, the entire flow has been heavy and black, and I have passed out twice. I do have a mirena. What is going on?

So you passed out, and did not rush to the ER ? Why ?

You need to see your doctor, no one online can do blood tests, exam and more that you need.
See your doctor and I would do it quickly