Hello dear I understand your concern Postinor 2 is highly effective (95-96%) in preventing the pregnancy as you took immediately after the sex. So there is 0-4% risk of the pregnancy. Nausea and dizziness could be due tot the pill and does not indicate the pregnancy. It is to early to tell about the pregnancy. Pill also cause delay in period by the 8-10 days. If period will delay by the 12 days then go for urine pregnancy tests and or blood HCG to rule out the pregnancy. If you will be pregnant then still you can use abortion pill under the advise of gynecologist to terminate the pregnancy. Meanwhile avoid stress, take healthy diet and do regular exercise. Take small frequent meal Hope this may help you Contact HCM for further health query Best regards Dr. Sagar