Mice are sentient, does that mean we should only use no-kill traps and then release the mice somewhere far away? Many urban pests have population numbers that are 50-100X higher per square mile in the city than they could sustain in the countryside. So if we could even theoretically capture them and release them in the countryside, most would die due lack of sufficient food, which also seems unethical. And simply releasing a pest on the other side of the city so it isn't bothering your house clearly isn't solving the problem.
Killing animals, particularly pests, seems like an inherent part of urban living. Is this unethical? I don't think so.
You haven't really given much rationale beyond "they seem to react to stimuli". At best, your position that they have consciousness or feel pain analogous to humans appears based on intuition; at worst, on dogma. Neither is a particularly reasoned stance.
My personal choices aside, there are also reasonable arguments against it that I don't think we should immediately dismiss with hand-wavy anthropomorphic arguments.
Hopefully most people can agree that when the turtle is flinching 30 minutes after death, it is not actually "feeling pain", despite reacting the same way that a cow or a dog or does. The argument that "it behaves the same as a cow/dog/human" is flawed. Anybody who's butchered a chicken or a fish can tell you that they can react as if in pain even after they are reasonably considered to be dead.