Have Had Floating Stool For Over A Year. Had A

Have had floating stool for over a year. Had a colonosapy in May and everything was ok. Continued to have floating, hard to flush stool. Now I have weak, achy legs 24/ 7 which have been getting worse. Never goes away but some days they feel worse than other days. If I take my Synthyroid medicine, 25 mcg my legs get worse so I have to take half of what I should take. This also happened last Spring. I have an appointment with a endocrinogist and a gastroalogist in March. I feel all are related to the stool. My regular Doctor said she didn't know, The endocrinogist nurse doesn't feel the Thyroid medicine is causing the leg pain and the Gastroalogist doesn't feel the stool is causing the leg pain. But I have office visits for both in March. I am worried about not taking the right amount of thyroid medicine and worried about my legs getting worse. I have already tried different Thyroid medicines, even Tirosint and my legs hurt too much to take the full am't I'm suppose to take.