All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
You are obliged to repent and seek forgiveness for what you did, because you have wrongly committed an aggression against a creation of Allah. The jurists are unanimous that whoever aborts a fetus should give a young male or female slave as blood money to the guardian of the fetus. The evidence is that Abu Hurayrah narrated that “Two women from Huthayl fought with each other. One of them threw a rock at her opponent and thereby killed her and her fetus. The case was brought before the Messenger of Allah, sallallaahu ‘alayhi wa sallam, and he ruled that the blood money for the killed fetus is a young male or female slave.” [Al-Bukhari and Muslim]
The scholars said, “In case no young male or female slave is found, the value of that, which is 1/10 of the blood money of the mother should be paid.” The scholars also agree that this designated blood money should be paid in the case of an aborted fetus whose limbs started to take human shape, because, in that state, it is known that it is becoming a human being. However, they differed on the ruling if the abortion happened before the fetus had started forming limbs. The preponderant opinion in our view is that whenever the fetus has passed the stage of Nutfah (mixed drops of the male and female discharge) –which means having passed the first forty days and entered the second forty days –the stipulated blood money should be paid if it is aborted regardless of whether it has become a clot, a lump of flesh or any other thing. This is because, the formation of the parts of the body starts at the beginning of the second forty days of the life of the fetus. The evidence for this is that the Prophet, sallallaahu ‘alayhi wa sallam, said: “When 42 nights pass over the creation of a Nutfah, Allah Sends an angel to it, who gives it form, and creates its ears, eyes, skin, flesh and bones …” [Muslim]
Since the formation of the fetus is hidden and the science of recognizing that was unknown to the people of the past, then those who considered the formation of the limbs as a condition for imposing the blood money among the early scholars did not rely on that science to determine the beginning of the formation of man. But nowadays, modern equipment (like the ultrasound machine) does confirm that formation starts in the stage mentioned by the above quoted Prophetic narration. Since it is known when human formation begins (i.e. the start of the second forty days of the formation of the fetus), then in our view, the preponderant opinion is the ruling that blood money becomes obligatory on anybody who aborts a pregnancy at that stage.
To conclude, you committed a sin that makes it obligatory on you to pay the blood money, which is a young male or female slave or the value of that, because the abortion took place after the second forty days.
Allah knows best.