I feel like everythings wrong with me?

ok i have headaches BAD.. unreal pain in my neck.. i got xrays and there fine. i really think i want a scan but the doctors said they dont want to expose me to unnecessary radiation.. my heart is fast all the time and iv an upset stomach most of the time... ok so i was told i had generalized anxiety about 5months ago. i went on tablets for a while and i am off them now for about a month as i dont want to become dependant on them... what i want to know is, is it possible that all these things that are wrong with me are caused because of anxiety or should i demand a scan????