I have been getting severe headaches frequently. I have observed generally when I bend my neck for a long time or during a train journey if I am sitting with an uneven back, it is triggered. It impacts the front part of my brain along with eye pain and nauseous feeling. Sometimes I feel like puking but it doesn't occur. When I press my neck it hurts. And it usually goes away after I take a nap. How should I handle it at home and when to see a doctor.