Disavowed

By the author of Manhattan Transfer, Redshift Rendezvous, and Naught for Hire

Star Storm is sent to a remote planet, to show massive force and keep a maverick government in line. Unfortunately, the ship attacks the wrong planet, one equipped with surprisingly powerful weaponry. Star Storm is destroyed, and the only survivors are Medical Officer Nick Sparrow and his AI, Natalie.

When Nick reaches the planetary surface in an escape pod, he's the alien invader. Nick struggles to survive, managing to befriend two dog-like aliens who run afoul of their own government. 

Nick could sure use some help, but none arrives. People at home hope Nick will never be heard from again. But they don't know Nick.