How can you tell if it is your period and not implantation bleeding?

Take pregnancy test: If you're having early pregnancy bleeding it may be different to your 'normal period' in amount of bleeding (heavier than normal or lighter than a normal period) or in timing - pregnancy bleeding usually occurs after the time your period was due. Symptoms are not 100% reliable - take a pregnancy test if you are late with your period or if your bleeding is different to a normal period.