Hi, ever since April I've started showing symptoms of hyperthyroidism, and that's when I first went to the hospital, as I had trouble breathing, my breath would be trembling and my hands and muscles would shake terribly and i had heart palpitations. At the hospital they gave me an ecg and a blood test, and apparently everything was normal (platelet count very high, neutrophil count elevated, lower serum ferritin level). I was told that it's completely normal for my age (18) to have heart palpitations, however this has been happening since April until now-December and it has only been getting worse. Recently, I have been to poland and there i received a TSH level result of 0.503, and in April it was 0.22 (normal range is from 0.4). Over the course of these months I've been to the hospital a few times already and the last visit showed arrythmia and the doctors want to do an echo to rule out myocarditis/pericarditis, as when I have chest pains the only way to get relief from it is to lean forward because it gets worse if I lie down or sit. Over the last two or three weeks I've lost 8kg instantly and the doctor is sure that I have hyperthyroidism, as I have all the symptoms (weight loss, irritability, shaking hands, muscle weakness, insomnia, heart palpitations and the feeling of chest pains, tiredness throughout the day and recently I've been told that my eyes have gotten enlarged, my eye sight has gotten slightly worse and more blurry at times). In April my TSH level was 0.22, in October 0.503 and my serum free T4 level was 12, free thyroxine level 14.8. I was told that this is all caused by stress, although there have been no changes whatsoever in my life and I am definitely sure that I am not in any stress. So I just wanted to ask what should I do next, as these symptoms seem to get worse and the doctors don't want to do anything to find out the cause for these symptoms. Also, I wanted to find out if those results are in fact "normal".
Thank you