The Pages of Time — Damian Knight

After suffering a traumatic brain injury in a shocking terrorist attack, sixteen-year-old Sam Rayner wakes from a coma to discover that he has developed seizures during which he is transported into the body of his past or future self. Can Sam and his friends somehow defeat the sinister forces that want to use his powers for their own ends? Can they manage to save Sam's family from violent deaths that are already in the past - and maybe also win the girl he loves - by turning back the pages of time?