What Causes Severe Headaches With Vomiting?

Hi, I have had a severe headache for the last 3 days. My whole body is aching and for the first two days of my headache I have been throwing up. The pain in my back between my shoulder blades right up to my neck is excruciating and feels like it is going to snap. Please can you give me any indication as to what I can do to fix the problem. thanks