Why did you start to bleed again a week after your period ended?

There are two reasons for this that I know of myself. Possibly, if you were on birthcontrol either the pill and missed one or more pills or a mirena and had it taken out and it made you have another cycle once you had it taken out......or in the case that you were not on Birth Control of any kind, had a regular cycle, and started bleeding again a week later......you're pregnant. That was implantation bleeding. Ive experienced all of this over the past few years....birth control can really mess with a woman's menstrual cycle and so can becoming pregnant. Either way, its best that you talk with a Doctor, because my degree is in psychology. Not Biology, or anything really helpful for this matter. Im only speaking off of my own experiences which coud have plenty of variables in each situation. I hope you're okay.