A drug delivery system for injecting a medicament includes a housing, a container configured to receive a medicament including a stopper configured to move within the container and a closure, a needle in fluid communication with the container, a spacer configured to be engaged with the stopper, a first plunger, a first spring configured to bias the first plunger in an axial direction, second plunger disposed about the first plunger, a second spring configured to bias the second plunger in an axial direction. The first plunger is configured to move the spacer and the container relative to the housing via the first spring to establish fluid communication between the container and the patient needle, and the second plunger is configured to move the spacer and the stopper relative to the container via the second spring.