I have had a stiff/sore neck (on the left side) for about 2 days. At first it felt liked slept funny on it but now it is very painful. In addition, I now have a severe headache that shoots pain in the front of my head whenever I stand up or make any sudden movements. It doesnt feel like a sinus headache or a migraine. I don t feel nauseous or have fever. Could the headache be caused by my stiff neck, and if so, how best to treat?