A tree secretes resin to seal the wound if you cut its trunk, but this doesn’t mean that it is suffering. A bacterium might swim away from a chemical or a temperature gradient it’s ill-equipped to survive; but this doesn’t mean that it is suffering. The existence of a self-protective or harm-avoiding response does not imply suffering.
To go even further, a spring returns to its equilibrium position when you pull on it and let go.
To go even further, a spring returns to its equilibrium position when you pull on it and let go.