What Causes Constant Low Body Temperature, Headaches And Hunger Pangs?

I ve been wrestling with what doctors have told me is anxiety/depression since June 2014 - but all the related medications I ve tried have resulted in all side effects and no benefits. My body temperature is constantly below 98 degrees sometimes as low as 96.2, I have stiffness in the base of my skull (where spine connects), headaches like I ve never had before, and a constant feeling of hunger despite eating. I should also mentioned that i ve lost about 30 pounds in the last year with the only change in diet being the total cessation of alcohol..... any ideas? I thought it might be related to the thyroid based on what I ve read....