What Causes A Change In The Menstrual Cycle And Foul Smelling Urine?

I am a 42 year old female who is in good shape. Ive suffered with throid disease for many years and have been taking synthrod and calcitrol for more than 20 years. Recently I have had a change in my period (10 days on 15 days off 10 days on....) and have a mettalic taste in my mouth and now I smell metal in my urine. HELP. I have a GYN appt next week but this is making me nuts