I know exactly how you feel friend, I was always suscpious Synthroid caused anger/anxious reaction. Done extensive research and yes Synthoid can cause various side effects/reactions. I have also read, that introducing or adjusting to Synthoid dose can cause symptoms, till hormones optimize.
But, best to have labs, rule out any lab abnormalities, keep a journal of symptom changes with dosing, discuss with your physician, try a different brand. Wish you well.
My mother was in remission for Hashimoto's but stress retriggered her Hashi's. I think she might be back in remission again.