From last few days I am suffering from weird one sided headache with sharp pain behind left eye and back side of the left head. Two days before in evening I felt like vertigo with small amount of dizziness, later that night suddenly sharp headache occured and it started vomiting it stayed for around 2-3 hours. From that day I have mild headache coming and going also can not concentrate on anything my left eye feels heavy and always feels sleepy but can not sleep even in night. Today I felt sharp wave of something in my backhead two times. So please help me regarding this. What to do next and is it serious issue? Thank you.