Neck pain on left side. I also get a pinching feeling in the same side of head and the back of head starts burning?

May be pinched nerve. If the pain that you feel is worse with bending your neck to the side and slightly backwards, it may be a pinched nerve (radiculopathy). The symptoms usually radiate to the arm or shoulder under those circumstances. If your symptoms are slightly better in that same position, then it could be myofascial pain or spasm. These indicators are not absolute but should be evaluated by your doctor.
Neck pain. Sounds like you have a pinched nerve, you might want to try some over the counter antiinflammatory meds like Alieve or Motrin and if that does not help then a consultation with a neurologist might be helpful.