Well I never had implantation bleeding so I can't tell you from personal experience... But from talking with friends/ladies on this board implantation bleeding is usually very light flow, red or brown in color, and only lasts from a hour or two to maybe a day. If it's getting heavier I don't know if I'd consider it implantation bleeding but then again maybe that is normal for you and it could be. Sorry I'm not much help ;-)