A veset haguf is a symptom that always appears a set time before your period begins and never appears at any other time. Therefore, if you ever experience irregular staining and it doesn't precede your period, then this would not be considered a veset haguf. Alternatively, if you ever get your period without this symptom preceding the bleeding, it would not be considered a veset haguf either.

If the only time you experience this type of staining is precisely two days before your period begins, then you may indeed have established a veset haguf. The next time you experience this particular type of staining, you would be required to observe an onat perishah two days afterwards, at the time you expect your period.

If your period consistently begins on Rosh Chodesh, on the same onah (daytime or nighttime), you may also have established a veset kavua for the day of the month. A combination of a veset haguf and a calendar-based veset is called a veset murkav (complex veset). If you think you may have established such a veset, please get back to us with details.

B'hatzlacha!