Dizzy spells with pain in the back of neck could be simply due to spondylitis of the cervical spine. An
X-ray or MRI can rule this out. Neck exercises, correct posture while sitting, and avoiding pillows while sleeping will help. What all tests have been done? If I had more detailed information, it would be useful in pinpointing the cause. Anemia, postural hypotension, migraine etc too can present with similar symptoms.