Accidental Werewolf by Aaron Pery
Price: $3.99 USD. 23190 words.
Published on March 15, 2011. .
While driving home, William and Margaret run into an unexpected storm and stop to install snow chains.
Just as he is done, Bill is attacked by a huge wolf, which Margaret kills but is attcked by another wolf that Bill is able to kill. But both were bitten.
That night at a motel, they find that both their bodies are changing into unknown young people, and realize that the wolves were werewolves.