New and confused about blood result

[pj16]

Hi. I've felt unwell with a long list of symptoms (which come and go, chop and change) for years. Many of my symptoms and blood results point towards autoimmune disease/s. My latest blood result is for Coeliac test and although I've tried researching in order to understand it for myself I have to admit defeat! I'm in the UK and my result is:-

tTG IgA Antibody (serum) <0.5 (a) kU/L (0 - 14.9)

Does this mean that I don't have Coeliac disease? Although I don't understand what I'm talking about could I be IgA deficient? Does IgA deficiency mean a total lack of IgA or can a very low result also indicate deficiency? I'd really appreciate any advice or comments please!