Elijah had been providing you with his blood for quite some time. It was a counter measure in case he wasn't around to provide protection. When you woke, his blood having sired you into a vampire, he had added to his sire line by one. It had been a very long time since the suit clad Mikaelson had added anyone to his sireline directly.

"Drink this. It will help you complete the transition."

Elijah produced a blood bag, holding it out for you to take. His brown eyes was calm, his face stoic of emotion. As you had no daylight jewlery, he would provide it when he was sure you wouldn't cause trouble. You were very much a fledgling in his eyes.