I had my mirena put in feb 28th, 2011.. I bled for 2 weeks and then not even a discolored spot... Everything was fine until a few months ago, I developed a bacterial infection which I visited my doctor and was perscribed antibiodics for, I finished the dose and was OK for a few weeks, then it cam back... I have been experiencing discharge and a horrible odor for 2 months now.. a month ago I had severe cramps which were so bad I was curled up on the bed crying in pain, they were accompanied by nausea and vommitting for two nights in a row, then stopped... Two days ago I began spotting and cramping(not horrible just noticable) but ite spotting is increasing... I have alos niticed that I have been having mood swings and may be developing a little bit of depression --{**the severe cramping and the spotting both began around 7 pm and lasted for an hour or two, but the spotting has yet to stop.)oh & I've taken countless pregnancy tests with negative results

What could be going on? Could I be pregnant and the tests just not show it?