Hi welcome to Health care magic forum, you are not specifik about your age, and personal details. If you are a student, it could be due to indigestion
, exertion, food poisoning
If you are a teacher either hypertension
, exertion, etc might be the cause.
Some people may get shaking hands, and body when they feel nausating , some may get blood tinge when they vomit. Some may get vomiting
due to leakage of blood in the stomach, due to hyper tension, peptic ulcer
I advise you to consult a physician for examination , investigation, diagnosis and treatment.
Avoid taking more of spices, chillies, junk foods and oily foods. dont worry you will be fine, and thanks for caling.