Yes during the start of 2014 my T levels were incredibly low for someone my age (22). My doctor said they were that of a 60 year old man and then prescribed with with a shot of Testosterone. As far as my symptoms were concerned I didn't really experience much in the way of brain fog just lifting away but generally I felt more energised.
As for vitamin K, could you please tell me what you mean by that? I don't take any vit K supplements..