Described is a medicament cartridge comprising a housing having open proximal and distal ends, a first coupling mechanism, and a syringe slidably disposed in the housing. The syringe includes a needle and has a retracted position in which the needle is covered by the housing and an extended position in which the needle is exposed. A delivery device comprises the medicament cartridge, an actuator comprising a plunger, a motor adapted to translate the plunger, a second coupling mechanism adapted to detachably engage the first coupling mechanism, and a control button adapted to actuate the motor. A carrier comprises a first slot for at least partially containing the actuator, a second slot for at least partially containing the medicament cartridge, a user interface adapted to provide at least one a visual signal and an audible signal.