bleeding is not a common finding, if occurs usually that can be seen around 1 week after fertilization, that could be minimal in quantity,
so if your bleeding period correlates with the possible time of implantation, and if the bleeding subsided soon, you wait till the expected date of periods and undergo blood or urine test for pregnancy
to detect the possibility,
bleeding due to miscarriage
will be rather heavy and usually presents with associated pain abdomen.