I had lost weight last year after starting my new job and this year still all the same eating habits and I walk 5+ miles a day and go up and down 6 flights of stairs a day I gained back the weight I lost. Does this sound like a thyroid issue and if so what test do I need to have done to get checked I also have pcos which I am on medication for and I am not pregnant as I take birth control religiously since I was 19.