@Appu: No need to see a doctor for slight bleeding and cramps. If your periods are still more than a week away, then this could be due to implantation bleeding. It is suggested to take the pregnancy test 1 week after the missed period. Even the doctor will not be able to detect so early, so better relax and just enjoy your upcoming days. In case the bleeding persists for more than 1-2 days, then it might be early periods.