Steel Time, by J.L. Gribble
Book 4 in the Steel Time series.
You're never too young or too old to experience a paradigm shift.
Toria Connor is 25 when tripping over an artifact in the ruins of Nacostina thrusts her a century into the past, before the city is destroyed during the Last War. Now, she finds herself alone. Adrift in a time where she must hide everything important to her, from her mercenary career to her true magical ability.
Victory is over eight centuries old when she follows her adopted daughter. She has seen empires rise and fall, but never anything like this. She must survive alone in a city inhospitable to vampires, dodging friends and foes from her past alike.
Both of them know the clock is ticking down to the moment when the city is wiped off the map.
Now, they're in a race against time. To find each other. To escape the past. And to save the future.