My Vampire System: A Dragon's Revenge

I was originally the apex predator that stood at the top of the world—the legendary red dragon. For thousands of years, my countless brethren have been murdered by humans, and revenge slowly turned into my only reason for living! In the end, however, I failed. On the day of the final battle with the humans, I was slain, and died with vengeance burning in my heart...If there were another life, I would definitely avenge my kind! If there were another life, I would make those filthy humans pay for what they've done! If there were another life... Huh? I got reincarnated as a feeble human child?