Is the light brown discharge that appeared after Maghrib, then the dark brown discharge, then the red discharge that appeared the following day considered menstruation? And should the prayers that were missed after first seeing the red discharge be re-offered? And when is a woman considered to be menstruating based on these symptoms?

If a woman sees a yellowish or brownish discharge (kudra) during her customary period, it is considered menstruation, and she should abstain from prayer. However, if the kudra occurs outside her customary period, it is not considered menstruation, and menstruation begins from the first sight of blood. The prayers that the woman missed after seeing the reddish fluid (blood) do not need to be made up, because that is considered menstruation. And not feeling menstrual pains does not prevent it from being menstruation if it occurs at a time suitable for it.