Hi. I was diagnosed with an under active thyroid two years ago and put on Levothyroxine 50mg. After a while I developed chest pains and my Dr. Didn't associate it with my Meds. I decided after two yrs to stop taking my Meds and they said to re test my blood in two months. I'm wondering if long term damage has been done to my heart because I just don't feel right at all. I feel really light and shaky when I walk and pressure in my chest that keeps being passed off as anxiety. I don't believe it is and think something is really wrong. Is it dangerous to just stop taking it? Any help would be appreciated.