It is indeed a matter of concern if your bleeding is continuous, as you say, for about an hour. Please report to the emergency immediately to get the bleeding controlled; it could be possible that the endometrial lining may have been shed and this need not lead to excessive bleeding unless there is a polyp, infection or a myoma
, or some hormonal
factor. The exact cause should be identified after the bleeding is controlled. Please get further support from your consultant. Hope this helps.