What Causes Shoulder And Neck Muscle Pains With Eye Pain And Headaches?

I have been having muscle pains in my shoulders and neck for two years and doctors can not tell me whats wrong. Now I am also having Severe headaches that come on with a pain behind my left eye. sometimes I just have the eye pain. I am not sure what type of doctor to see as I am not sure what may be going on. I also have weakness in my feel and leg and it can take a minute to get my balance.