mirena IUD

hi, i am a new mother to a two month old baby girl. at my six week check up i had mirena IUD put in. since then i have been bleeding pretty much every day. that so far is my only complaint about mirena. today i got up as usual. i went outside and came back inside only to feel very dizzy, almost like i was very very drunk. the room was spinning i couldnt walk straight. so i laid back down and i go to the point where i couldnt even raise my head i was so dizzy. my first thought was anemia or vertigo. i called my doctor and the nurse said it wasn't mirena or the zoloft. but im not so sure. what are your thoughts on this??