She is not sure whether she went out of Islam; does she have to do ghusl?
Question

If a woman becomes Muslim during her period, is it acceptable for her to do one ghusl for both purification and entering Islam, after her period ends? If she became Muslim shortly after her period ended, a few hours or one day later, is it the same as the first case, and is it acceptable for her to do one ghusl for purification and entering Islam? I am Muslim, but I am not sure, I think I may have said something that made me a disbeliever; I repented to Allah and renewed my Islam before doing ghusl after my period ended. I am asking about these two cases, because it was at the end of my period, and I did not know whether my period had ended or not, so I do not know whether I renewed my Islam before the yellowish or brownish discharge had completely ended, or after that. Is there any difference in either of the two times when I renewed my Islam? I also remember that I have read that there is a difference if a woman becomes Muslim during her menses or after it, but as I said, I do not know when. What must I do? Can I do one ghusl with the intention of purifying myself and entering Islam?
Praise be to Allah.Firstly:
What appears to be the case is that you are afflicted with the sickness of waswasah (intrusive thoughts or whispers from the Shaytaan), based on previous questions that you have sent to our website. Our advice to you and to others who are affected by this sickness is to ignore the waswaas (intrusive thoughts) and pay no attention to them. Ignoring the intrusive thoughts is one of the most beneficial and effective remedies, after seeking refuge with Allah from that. Al-Bukhaari (3276) and Muslim (134) narrated that Abu Hurayrah (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) said: “The Shaytaan may come to a person and say: Who created such and such? Who created such and such? Until he says to him: Who created your Lord? If it goes that far, let him seek refuge with Allah and stop (such thoughts).”
Al-Haafiz Ibn Hajar (may Allah have mercy on him) said: The words “Who created your Lord? If it goes that far, let him seek refuge with Allah and stop (such thoughts)” mean: let him stop getting carried away with such thoughts. Rather he should turn to Allah and ask Him to ward them off, and he should understand that the Shaytaan wants to spoil his religious commitment and spoil his reason by means of these intrusive thoughts. So he should try hard to ward them off by focusing on something else.
End quote from Fath al-Baari (6/340-342).
For more information on the topic of dealing with waswasah, please see the answers to questions no. 39684, 12315 and 10160.
Secondly:
The question of whether one has apostatized and gone out of Islam can only be determined on the basis of certainty. Based on that, it cannot be determined on the basis of what one is uncertain as to whether it is a cause of disbelief, because the basic principle is that a person remains a Muslim, and a Muslim does not apostatize from his religion unless he says or does or believes something that the Qur’an and Sunnah indicate constitutes major disbelief (kufr akbar) that puts a person beyond the pale of Islam, or concerning which the scholars are unanimously agreed that it constitutes major disbelief.
As that is the case, a specific person cannot be deemed to be a disbeliever unless the conditions for deeming him to be a disbeliever are met and the impediments to doing so are absent in his case. One of those conditions is that he should be an adult of sound mind and free will, who cannot be excused on the basis of ignorance or misinterpretation, in cases where ignorance or misinterpretation may be taken as an excuse. Based on that, if a person is not deemed to have apostatized, he cannot be asked to do ghusl, because apostasy must be proven first of all, and that is more applicable in the case of one who is affected by waswaas.
Moreover, with regard to ghusl for a disbeliever who becomes Muslim, or an apostate who returns to Islam, that is a matter concerning which the scholars (may Allah have mercy on them) differed. Many of the scholars are of the view that it is mustahabb (recommended), not obligatory.
This is been discussed previously in the answer to question 81949.
Based on that, you only have to do ghusl following the end of your menses. May Allah protect us and you from the whispers (intrusive thoughts) of the accursed Shaytaan and keep us safe from his tricks, for He, may He be glorified, is able to do all things.
And Allah knows best.