flirtygerty. I sympathise as i have severe health anxiety and i only have to have a headache and ive got a brain tumour!
To me, it sounds like you are run down, or there is some hormonal problems. Whomovedmychocolate, you raised the issue of cortisol and i think you are right. Changes in cortisol can lead to all of the issues flirty mentioned, the dry hair is what makes me think of that.
One of the main things that can alter cortisone production is stress and anxiety, which is why the symptoms manifest physically as well. I think you should go back to the doctors and ask to see a different doctor if you can.
Can i ask a sensitive q? Did you ask your D if he thought you had cancer? If you did, he probably feels he has done his bit by reassuring you that what you describe doesnt sound in the slightest suspicious.