What Causes Odorous Vaginal Discharges With Stomach, Back And Leg Pain?

I had the mirina removed on feb 28th and started my period on March 2nd. so by my count i should have started on the 30th and i havent. I took a pregnancy test because my husband and i have been trying to have our 3rd child. and anyway it came up negative. im experiencing lowerback and leg pain and my stomach is tender. i am also haveing vaginal discharge that smells like amonia. is this a side affect of the mirina or am i having a possable miscarage like i did back in 08