Pain & nausea on Mirena

I've had the mirena since the beginning of May (4 months) a couple of weeks after getting it fitted I had some spotting but have not had a period since before it was fitted. Since then I've had a brown discharge, lower back pain and felt nauseous. In the last week this has gotten far worse to the point that I've been off work experiencing intense pains in my lower back and abdomen and feeling really nauseous. Has anyone else experienced this on the mirena? Tweet