Hmm they must be testing you for other possiblities as well, since you are not allowed to eat, it will be good for you to have a complete blood works done, just to elimnate anything, sounds a bit like you are low in Iron, I too have that problem, luckily it is usually easily fixed with either supplements and a change in diet, good luck, honestly it does not hurt much, I used to be scared of having blood tests as well, now I just don't worry about them anymore, and usually it is relatively painless. GOOD LUCK all the same and keep us posted as to how you go ok.