A potent conjunction of the stars and planets occurs on your birthday. you are struck by a falling star which passes through your body like it was made of mist. you awaken feeling different, as if something has been awakened from within.
Martial training: In adolescence you trained with the weapons of your people and learnt how to use them proficiently (work with your DM to determine details)
When you become an adult you learn to used a weapon (of your choice) appropriate for your culture and social standing. (work with your DM to determine details)