17 year old female. I was diagnosed w/ thyroid cancer when I was ...

17 year old female. I was diagnosed w/ thyroid cancer when I was 8 and had my entire thyroid and several tumors removed a month after the diagnosis. I've been on Levoxyl for about 7 years. I often experience chest pain, nausea, abdominal pain, and depression. I want to take myself off the medication, because I recently went 3 weeks w/o taking it and the depression went away. Only problem is when I stop taking the medication for more then a month I start to feel really sick, paranoid, and I'm unable to concentrate. I've asked my mom if we could look into an alternative medication, but she believes my doctors when they say that my depression, chest pain, nausea, and abdominal pain are not at all related to my taking Levoxyl.