Don't know what happening or what it is i've had two years of neck pain day and night rigidity trouble moving left to right pain up and down my neck. ?

Exam/x-ray/PT: Get a medical exam and cervical spine x-ray. You may have muscular spasm or arthritis in your neck, spinal impingement or other disease. Do not ignore these symptoms.

Spasm : It may be spasm. When spasm occurs, pain and limited range of motion can follow. Sometimes it can be related to simple overuse or strain, sometimes there can be a serious underlying condition causing it. Don't hesitate to be seen.