Hello Welcome and thanks for asking Stomach pain during menstruation is called dysmenorrhoea and there is nothing to worry about , you should not stop normal activities due to pain , more pain plus vomiting can be due to stomach disorder like acidity associated with menstruation for which you can take antispasmodic like meftal spas one tablet and antacid along with , if still persists you can get investigated like ultrasound abdomen Take care Best wishes