Has ANYONE noticed a change in bowel movements/bloating since bei...

Has ANYONE noticed a change in bowel movements/bloating since being on the Mirena? Ive had it since August of 2008 and since then I have gained 20 lbs, ALWAYS bloated and my bowel movements have changed in consistency. My doctor has sent me to have blood work, CAT scan of abdomen and a colonoscopy and the results where all negative. At this point I have NO DESIRE to have sex, Im 42 and don't want anymore children and cant take regular birth control due to migraines. But at the end of each day my ankles are swollen and I feel huge?? Anyone with LIKE symptoms?