A discrete pest-natural enemy population model is built with multiple insecticide sprays within a generation. First, the Jury criterion is used to investigate the existence and stability of boundary equilibrium points and the existence of nontrivial equilibrium points. Then, this paper explores the effects of spraying time and instantaneous kill rate on pest control, and gives the conditions for the paradox of pest control strategy. Then it is examined about the role of continuous incorrect spraying of insecticides on pest outbreaks. The results show that incorrectly spraying insecticides multiple times within each generation of the pest can trigger more severe pest outbreaks. Finally, numerical simulations are conducted to verify the findings are conducted.