Hi Im hoping I can get some advice,

For Over a year now Ive been getting a short sharp shooting pain in the back of my head almost like I have been stabbed, then a week ago saturday I had a severe dizzy spell and didnt feel well afterwards, that night I had severe vivid nightmares and I woke up with palpatations and was still dizzy ,

since then I havent felt well atall, I had diaoreha which has now passed , thumping (but not fast) heart beats , dizziness , unable to walk far, sore lumpy breats, flu like feeling but not blocked up nose or coughing, my head feels like its crammed with cotton wool, ive been unable to think straight or remember certain things.I also find that after I eat I feel really tired and dizzy and alot worse, (although I have noticed this over the past few months but never as severe as it is now)

Im having trouble sleeping but then feeling exhausted throughout the day needing to sleep a few hours. Also as Im falling asleep my heart feels like its skipping a beat.

Ive been back and forth to my GP who said I am dehydrated but each time I go my dehydration is getting better , he ran a series of blood tests on me (thyroid disease was one of them) and an ecg , all came back normal apart from my white blood cells which he said is high, but isnt going to run any further tests on me, he prescribed me antidepressants which I havent started taking yet as I dont feel im depressed other than worrying about whats wrong with me.

I woul really appreciate some advice as I am really worried and cant get on with my life at the moment, I have also been tested for diabetes in the past which came up clear.