Left over blood from your period, hormonal imbalance, pregnancy etc
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Yes more than likely, you have nothing to worry about.
Could be you are spotting. Especially if on birth control and missed a couple of days.
Menstrual period refers to menstruation or your period, which is the start of your menstrual cycle. If you're referring to mid-cycle then midway through the menstrual cycle is typically when a woman would ovulate.
that's normal.. don't worry about it.
Menstrual cycle refers to your entire reproductive cycle, so you would always conceive during your menstrual cycle. If you're asking if you can conceive the first day after menstruation then the answer is yes, there may be an egg present that early in your menstrual cycle.
Four B12 shots usually will not cause your menstrual cycle to be late. Your cycle can be late if your body is low in vitamin B12. You should talk with your doctor and ask him why your menstrual cycle would be late
Pregnancy can cause this spotting or irregular periods or a UTI.
No. This would be considered highly unusual.
Your period..............maybe or skid marks
The menstrual cycle is the reproductive cycle, this is when a female would conceive - I think you mean two days after her period. Yes, a female can conceive two days after her period if her cycle is short.
To stop your menstrual cycle from starting, you can consider getting on birth control. It would also be a wise idea to maybe consider an IUD.
Some women have spotting during ovulation, if your cycle is very regular the timing would be correct for this to be the cause. See your doctor or midwife if the spotting continues.