You must not take ghusul until you see your purity which is recognized by the white thread like discharge or by total dryness.

im confused about periods, on the 7th day the blood finishes and I see browish resideu and then yellow, on the 8th day in the evening I had ghsul and then then the next day I saw some yellowish residue that I see after period but it was not there on that day, is my fast and prayers not accepted? Do I have to redo my ghusl? If one sees brownish yelloish after blood is ghusl valid