Hi all it is my first post on here and I wanted to say I am glad I am not alone. I do not understand all these blood tests as I had a breakdown in December but over it now do not know why it happened. I was called into my GP two years ago who told me my yellow serum was low, I asked what that meant and she responded by turning her computer screen round saying you T3 is almost out of the box. She gave me leva thyroxine to take 50mg told me I had to take it the rest of mt life. Well that was all nothing else was explained to me. My usual GP was away so I could not see him I was lost. I lost my mum whom I cared for in the December lost 3stone but I also had the test around hat time so I thought it was because of that. I feel so unwell all the time. Please can you help me just by listing what not having enough yellow serum means in English. All the simptoms of this hen I can wipe out by treating what is not caused by it. Please help me I have had the blood test 4 times now and there is no change.