What is the ruling on making up the days during which I did not know the correct sign of purity, and do I owe expiation if Ramadan begins and I have not completed the make-up?

The sign of purity is dryness or the white discharge. Yellowish discharge connected to menstruation or occurring during its time is considered menstruation, but yellowish discharge after purity is not considered menstruation. There is no need for a make-up (qada') unless one is certain that the act of worship was invalid. One may be excused for ignorance in such matters. It is permissible for someone with obsessive thoughts (waswas) to adopt the easier opinion. Expiation for delaying the making up of Ramadan fasts is obligatory for whoever delays it without a valid excuse, but not obligatory with an excuse.