Desperate to talk newcomer

Hi,my names Dave,55 years old and sitting here writing this post at 6am after a night of sleeplessness and anxiety. I have always suffered from anxiety as far back as I can remember as a child and has now developed into some of the worst symptoms I have known.Constant head pressure like my head is going to explode,head zaps mostly when I shut my eyes,GERD,stomach problems,tingling in hands,back pain,chest pain,facial nueralgia,flu like symptoms coming and going,panic attacks out of the blue,constant irrational thinking,fear,despair and depression.There are other symptoms that come and go too. the doctor has put me on"Citalopram" for depression and I am not sure If this is working as only been on it for 5 weeks.The doctor says my symptoms are the worst reaction"Psychosomatic"to stress he has known.I am desperate,feel alone and at times struggle into another day wondering If it will be better.I long for a few hours of restful sleep and that tomorrow I may feel "normal" once again. I have often thought of how easy it would be to press a little button and not exist anymore to remove myself of this terrifying existance.I have searched the net and found this site,hoping to find others who have experienced the pit of despair that anxiety can bring and that I'm not alone.I do hope someone will make time to speak to me and offer some reasurance that I'm not going mad,that anxiety disorders really can overwhelm ones senses and cause all these symptoms.Thankyou!