Book Writing progression?

I am stuck in my story. The part ends with the oldest immortal girl leaving her house with one of her old friends from her homeland (also immortal, if you haven't gathered that already). The new immortal is in her bedroom with her human friend whom she just revealed herself to. At first i was thinking about making the old friend actually like a henchman for the antagonist, but it would be weird for the newly turned immortal to have to save the experienced, magic, 200 year old immortal that close to the beginning. It will happen eventually, but she has to be trained first. Another idea i had was from the humans POV, something like "A few weeks had gone by since i found out about _______." I thought it might work, but i'm just not sure if that would be the best way to go. Any help?