Am I exempt from the Udhiyah because of my ignorance of the number of sacrifices and their timing, or must I slaughter again?

The ruling on Aqiqah has been clarified as a confirmed Sunnah, and it is slaughtered on the seventh day. If slaughtered before the seventh day, it is still valid, because it was performed after its cause, which is birth. The sacrifice for a boy is two sheep, and for a girl, one sheep. The Malikis and those who agreed with them held that it does not multiply, and one sheep is sufficient for every newborn, whether male or female. The scholar Khalil al-Maliki said: "And it is recommended to slaughter one sheep that suffices as a sacrifice on the seventh day of birth, during the daytime." This is based on what Abu Dawud narrated and Al-Albani authenticated from Ibn Abbas, may Allah be pleased with them both, that the Prophet, peace and blessings be upon him, sacrificed one ram for Al-Hasan and one ram for Al-Husayn. So, what has been done is sufficient and fulfills the Sunnah of Aqiqah, even if it is contrary to what is preferable.