36 yo, severe pulsating headache on top/bck of head accompanied by uncontrollable shaking as if cold. ceased after vomiting. should i be concerned?

Headache : Definitely need to see a doctor. Especially if you don't have a history of migranes or headaches. I assume no recent head trauma.

GO IMMEDIATELY TO ER: You have alarming symptoms.PULSATING HEADACHE, CHILLS AND VOMITING Any history of ;headaches, trauma, systemic disease,Pregnancy,? New symptoms such as a fever, weakness, vision loss , double vision, or confusion? Are you taking medications? It can be any where from life threatening condition, such as meningitis, brain infection, aneurysm, bleeding, mass, etc. Of course it can be migraine, etc.