I am 25 years. It has been 6 weeks, (June 21st 2018) on a Thursday night, I was laying in bed and I suddenly got up with a terrible panic attack due to feeling of suffocation. It took me a few days, thinking and hoping I would feel better. But I never did feel better, so I went to a GP. He told me it must be acid reflux causing me to feel that way, and even did H.pylori test and urine test. Everything came back normal. I wasn't getting better even with the omeprazole. Another doctor told me that I must just have anxiety disorder. But a friend of mine convinced me to go see another doctor, sadly in my country we don't have any endocrinologist, therefore I went to an internist, intensive care doctor that was highly recommended. I explained my symptoms to him (2weeks after the first time attack), symptoms are: heart palpitations, extreme nervousness, and dyspnea ( feeling like I can't take deep breaths, causing me to feel like I am suffocating- even when I eat therefore I lost so much weight because if I ate 1 time a day was a lot. I went down to 80lbs), I feel nauseous when I do eat, and burp a lot. Due to the anxiety, I hardly sleep. Take long to fall asleep with heart palpitation, and get up 4 every morning because nervousness wakes me. 
He made me do an ultrasound of the thyroid and a chest xray how I was complaining about the breathing. The chest xray came out normal. The thyroid showed 2 nodules slightly inflammated. So he ordered for me to do a blood test and there it was, my t3 was 54 ans the others were also off the range. So he placed me on Tapazole 5mg 1 time daily and 1/2 a propanolol 40 mg every 12 hours. So I was on it for 2 weeks, symptoms didn't go away, so I went to see him again, he ordered another blood test, Everything went back,on range except the tsh was going lower. He asked for me to do a spirometry test/bronchodilation test how I kept complaining about my breathing, and it came back normal. So,he increased the dose of the tapazole, from once to 1 every 12 hours. And the symptoms were going away. But it only lasted for a week or almost 2. Then the symptoms returned, not sure of it was because my period came down then. Either way, I decided to go to another internist/intensive care doctor at another private clinic for a second opinion. He asked me to do another blood test and this time it showed everything within range, normal. But the symptoms still there. So he decreased the dose to the original of 1 time a day of tapazole and half a propanolol every 12 hours. The symptoms have improved slightly but I still get every so often severe nervousness or find myself gasping for air and deep breaths.
I hope I get better soon! Today is 9th of August 2018.
I hope I get better soon. I just got a new job and can't miss days. I am a teacher.
--
Being anaemic can cause breathlessness - so check Iron - Ferritin - B12 - Folate and VitD. ALL need to be optimal.
Oxygen is transported around the body attached to iron in the red blood cells. When the heart detects lowered oxygen levels it beats faster to pump more blood and therefore increase oxygen !
Do not accept fine or normal - secure copies of your results and post here in a new post.
Hope you soon feel better ...
Thank you. Tomorrow I will post all my results.
By the way, did the blood test a month ago and it was normal. At 12. And since then been drinking vitamins to take it up due to the meds I'm taking. The Dr says I have anxiety. The spirometry test is to test the expansion/ capacity of the kings, and they always test the level of oxygen in my body as well as heart rate and always shows normal.
Which test was 12 & normal ?
My RBC was 12 so I have been taking vitamins. This 3rd time, after taking meds to suppress it, my thyroid t3,t4,tsh, t7 is in range now. If it weren't for the feeling of can't breathe well and nervousness, I would feel normal. I just want it to go away.
Do you know more or less how long the symptoms go away after the thyroid is stabilized?