I Have Many Problems.dinginess,tiredness, Sometime Totally Faint Unconscious(10min-30min) During Walking,

i have many problems.dinginess,tiredness, sometime totally faint unconscious(10min-30min) during walking, jugging and mostly wake up time.some time before going to be unconscious pain and burning hearth through and spinal backside of neck,i have gastritis and neck spinal dis pro-lac,I already checked and try to dignosis(ECG,ECO,NGIOgraphy, MRI,EEG,chest X-ray but not diagnosis why?blood test,blood sugar ,blood presser everything lab test are normal.what to do ?