@Pranaya: Since you're still about a week away from your periods, so this pain is neither a period pain or early symptom of pregnancy, it might be due to some indigestion. Try taking some antacids or Pudin Hara tablets.
@Pranaya: Implantation bleeding usually happens two weeks after conceiving. You might notice some spotting if it's implantation. You need to wait till your missed period to know for sure.