Is there repentance for me after I embraced Islam and committed adultery, knowing that I was a Christian?

It is from the mercy of Allah Almighty that He opened the door of repentance to His servants until the sun rises from the west. No sin is too great for Allah to forgive for one who seeks His forgiveness. Allah has called upon those who have transgressed against themselves not to despair of His mercy, for He forgives all sins. And from His mercy is that He did not place any intermediaries between Himself and His servants. Therefore, the servant must offer sincere repentance to Allah, seek His forgiveness, and do good deeds. The questioner must hasten to sincere repentance.