Mirena and grand mal seizures

Hi everyone, I had my mirena put in feb of 2008. Around June 2008 I started having dizzy spells, and headaches. Went to ENT and ruled out inner ear problems, went to neurologist and he said it could be migraines. I never had them before but have a family history. I have in the last couple months been having really bad dizzy spells and nausea, like 4-5 times a week. Has anyone else had any of these problems? Not sure if its the mirena or not, but have been to just about every doctor and no one can figure out why i have been so dizzy and nauseous> Any suggestions?????