Loss of cervical lordosis&reduced d. gap

I was  diagnosed from loss of cervical lordosis and reduced disc space C5-c6 by X - Rays prescribed by a Neurologist.My Neurologist recommended me ( Stemitil Md 5 mg, combiflam and Gabapentin - L gel for 5 days and certain exercises. The exercises mostly had neck tilting upwards and back. . Use of an adjustable cervical collar is also recommended. Kindly help with the following: 1.. when I do these exercises and tilt my neck backwards I feel dizzy. Is it normal or shall I stop the exercises and consult with other speciality.Read somewhere that this dizziness is normal and will subside as my body gets 2. Is there any advantage of an  adjustable cervical collar over a standard soft cervical collar? 3. Which will be the right specialist to treat these issues? 4. What can be the cause of dizziness while exercising. Kindly help