Does anything become incumbent upon me if I woke up and found semen, then performed ghusl and prayed Fajr five minutes before sunrise, knowing that I did not pray the Sunnah? And is it obligatory for me to make up the Sunnah of Fajr?

A Muslim must observe prayer at its prescribed time, and he may use an alarm clock or other means to wake up. If he wakes up a short while before the prayer's time expires, he must perform ablution and pray immediately, whether he catches the entire prayer within its time or not. Whoever catches one unit (rak'ah) of the Fajr prayer before sunrise has caught it as due performance (ada'an). As for making up the Sunnah of Fajr, it should be done after performing the obligatory prayer. If there isn't enough time for it before sunrise, then it should be done after the sun has risen to the height of a spear.