A self-injection device (100, 200), including a pen body (108, 208) connectable to a pen needle (10), and a cap (104, 204) selectively connectable to the pen body (108, 208) in a first orientation with respect to the pen body (108, 208) to minimize the length or volume of the self injection device (100, 200), and in a second orientation to provide sufficient length or volume in an interior of the cap (104, 204) to house a pen needle (10) connected to the pen body (108, 208).
